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ELM  EM  DOE  F 


DAVID  R.  ALLEN. 

Library  No 

Please  lE^etia-rn- 

1 


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RESEARCH  LIBRARY 
THE  GETTY  RESEARCH  INSTITUTE 


JOHN  MOORE  ANDREAS  COLOR  CHEMISTRY  LIBRARY  FOUNDATION 


Raymond  Petti  bon 


A 


Lantern  Slides: 


DWIGHT  LATHROP  ELMENDORF. 


Little  Book  ! Yield  enough  light  for  the 
reader  to  discern  the  author’s  humble 
attempt  to  lend  a helping  hand. 


PUBLISHERS: 

E.  & H.  T.  Anthony  & Co.,  591  Broadway,  New  York. 
1895. 


Copyrighted,  1894, 

BY 

E.  & H.  T.  Anthony  & Co. 


CONTENTS. 

Page 

Introduction 6 

Chapter  I,  The  Contact  Method . 13 

Chapter  II,  The  Camera  Method 41 

Chapter  III,  Diseases  and  Remedies 48 

Chapter  IV,  Testing  Slides 54 

Chapter  V,  How  to  Color  Slides 


58 


Digitized  by  the  Internet  Archive 
in  2016 


https://archive.org/details/lanternslideshowOOelme 


LANTERN  SLIDES,  HOW  TO  MAKE 
AND  COLOR  THEM.* 

INTRODUCTION. 

THE  difficulties  which  meet  the  beginner  at 
the  start  are  many,  and  though  some  of 
them  are  real  and  are  to  be  overcome  only  by 
care,  patience  and  perseverance,  yet  most  of 
the  obstacles,  which  appear  as  mountains,  soon 
disappear  before  the  magic  of  common  sense 
when  applied  under  the  guidance  of  practical 
experience. 

The  printed  directions  enclosed  in  each  box 
of  plates,  while  explicit  enough  for  one  well 
versed  in  the  art,  are  Greek  to  the  novice.  The 
formulas  puzzle  some,  the  names  of  the  chemi- 
cals, others;  the  chemical  actions  threaten 
distraction,  while  startling  results,  not  at  all  in 
accordance  with  the  directions,  cause  a total 
collapse. 

The  purpose  of  this  little  work  is  to  guide 
those  who  will  follow  its  directions  as  Alpine 
climbers  do  the  “ fiirer,”  step  by  step,  trusting  to 
the  direction  of  their  leader,  who  has  often 
surmounted  the  difficulties  which  lie  in  the 
path  leading  to  a perfect  lantern  slide. 

There  are  no  short  cuts  to  real  success,  but 
by  using  the  best  appliances  and  methods  we 


6 


may  speed  over  the  path,  enjoying  each  new 
difficulty  as  it  appears,  because  of  the  assurance 
born  of  past  successes. 

The  making  of  a lantern  slide  at  the  present 
time  is  comparatively  a very  simple  process, 
because  every  requisite  is  prepared  for  the 
worker,  ready  for  immediate  use,  and  no  knowl- 
edge of  chemistry  per  se  is  necessary.  The  re- 
sult, be  it  good  or  bad,  depends  entirely  upon 
the  “ personal  equation.” 

If  this  uncertain  quantity  were  known  in  each 
particular  case,  it  would  be  an  easy  matter  to 
prescribe  the  proper  treatment ; but  as  it  varies 
even  in  one  and  the  same  person,  the  following 
directions  will  only  apply  to  those  who  will  not 
insert  or  assert  their  own  personality  too 
much. 

It  is  taken  for  granted  that  the  beginner  has 
at  least  one  good  negative.  If  at  all  in  doubt, 
it  is  best  for  the  novice  to  have  some  one  who 
knows  select  a good  one  to  be  used  as  a 
standard. 

Long  experience  has  taught  the  author  that 
the  negative  is  the  first  stumbling  block. 

Not  many  really  know  what  a good  negative 
for  slide  work  is. 

One  which  is  rich  in  contrast,  yielding  a 
beautiful  paper  print,  will  make  a good  slide  ; 
but  it  cannot  be  compared  with  one  which  was 
slightly  overtimed,  and  therefore  a trifle  flat  for 
paper  prints,  but  clear  and  full  of  detail,  the 
chemical  deposit  or  grain  of  the  plate  being 
exceedingly  fine. 


D.  L.  Elmendorf. 

SANTA  MARIA  DELLA  SALUTE,  VENICE. 


7 


This  quality  of  negative  has  yielded  slides 
which  have  been  magnified  up  to  30  feet  square, 
and  still  the  lights  and  shades  were  beautiful. 

Lantern-slide  plates  in  this  country  are  3J 
inches  wide  and  4 inches  long.  Various  manu- 
facturers make  plates  of  these  dimensions, 
packed  one  dozen  in  a box,  the  latter  being 
carefully  sealed  in  order  to  keep  all  light  from 
the  plates.  The  plates  manufactured  for 
lantern  slides  are  generally  quite  thin,  and  the 
glass  is  supposed  to  be  especially  selected  ; but, 
alas,  there  is  plenty  of  room  for  improvement  in 
this  respect.  The  glass  is  coated  with  an  emul- 
sion of  silver  which  is  sensitive  to  actinic  light. 

By  actinic  light  is  meant  any  kind  of  light 
which  causes  a chemical  change  in  the  emulsion 
which  can  be  detected  or  developed  by  using 
proper  means.  Throughout  this  work  “ actinic 
light  ” will  mean  the  light  used  to  photograph 
with,  whether  it  is  sunlight,  gaslight,  lamplight 
or  candle-light. 

A rainbow  is  composed  of  seven  so-called 
colors.  One  edge  of  it  is  red,  the  other  violet, 
with  the  five  other  colors  lying  between.  By 
holding  a common  triangular  glass  prism  in 
a sunbeam  the  same  colors  will  be  seen  upon 
the  ceiling  or  some  part  of  the  room.  This 
beautiful  band  of  seven  visible  colors  is  called 
the  sun  spectrum.  Without  entering  into  a 
physical  discussion  upon  this  subject,  let  it 
suffice  to  say  that  the  glass  prism  decomposes 
the  white  (?)  sunlight,  or  separates  the  various 
colors  which  together  form  white  light,  so  that 


8 


we  can  see  seven  of  them.  If  a small  sun 
spectrum  be  allowed  to  fall  upon  a piece  of 
sensitized  or  silvered  paper,  such  as  is  com- 
monly used  for  printing  photographs,  it  will  be 
found  that  the  portion  in  the  violet  end  of  the 
spectrum  will  turn  brown  rapidly,  while  that  in 
the  red  will  be  hardly  affected  at  all. 

From  this  we  discover  that  red  light  has  little 
or  no  effect  upon  the  silver  compounds  used  in 
photography,  whereas  they  are  instantly 
changed  in  the  blue  and  violet  ; and  careful 
experiments  prove  that  there  are  many  rays 
beyond  the  violet,  which  the  human  eye  cannot 
distinguish  at  all,  that  are  especially  energetic 
in  their  action  upon  certain  chemicals.  The 
green  and  yellow  portions  of  the  spectrum  have 
some  chemical  effect,  but  not  nearly  so  much  as 
the  blue  and  violet. 

A piece  of  “ ruby  ” glass  (gold  flashed,  not 
copper),  held  in  the  sunlight,  absorbs  or  stops 
almost  all  of  the  colors  of  which  sunlight  is 
composed,  except  the  red,  which  passes  through 
and  gives  us  only  red  light,  if  the  glass  is  prop- 
erly flashed  or  coated  with  a film  of  red  glass. 

This  glass  is  the  best  and  safest  medium  used 
for  producing  red  light,  which  has  little  or  no 
chemical  effect  upon  the  sensitive  dry  plate  ; 
and  it  is  therefore  recommended  for  lamps 
which  are  used  to  furnish  light  for  developing 
the  ordinary  plates  prepared  for  general  photog- 
raphy. These  plates  are  generally  extremely 
sensitive  to  violet,  blue,  green  and  yellow  light 
in  their  order. 


9 


The  plates  made  for  lantern  slides  are  not 
nearly  so  sensitive.  To  use  a technical  term, 
they  are  “ slower  ”;  therefore,  ruby  glass  is  not 
necessary,  although  it  is  the  safest. 

There  is  a glass  called  “ dark  amber,”  which 
serves  admirably  when  backed  with  a piece  of 
ground-glass.  It  yields  a soft  brownish  yellow 
light,  which  does  not  try  the  eyes,  and  can  be 
used  without  danger  while  working  with  the 
slow  lantern-slide  plates. 

Sunlight  or  daylight  is  the  most  actinic  light 
that  we  have,  next  to  which  is  the  electric  arc 
light,  which  is  now  being  substituted  for  day- 
light in  many  of  the  best  studios.  Next  in 
order  is  that  produced  by  burning  magnesium. 

These  are  all  especially  rich  in  blue  and  violet 
light  or  actinic  rays. 

The  incandescent  electric  light,  gas  jets  and 
kerosene  oil  lamps  yield  light  which  also  con- 
tains these  actinic  rays,  but  in  a lesser  degree. 

The  difference  may  be  detected  by  using  the 
triangular  prism.  The  spectrum  of  these  is 
especially  rich  in  the  yellow  portion,  therefore 
the  light  from  these  sources  is  not  so  actinic, 
but  contains  enough  of  the  actinic  rays  to  act 
instantly  upon  the  sensitive  dry  plate.  In  fact, 
an  ordinary  gas  jet  is  the  source  of  actinic  light 
which  the  author  uses  for  exposing  the  slides 
in  order  to  produce  the  image  upon  the  plate. 

As  “ruby”  or  “amber”  glass  stops  the 
actinic  rays  of  sunlight,  they  will  also  stop  those 
in  other  sources  of  light  and  allow  the  red  light 
(non-actinic)  to  pass  through  so  that  the  opera- 


10 


tor  can  see  what  is  going  on,  without  injury  to 
the  plate. 

The  beginner  cannot  be  too  carefully  warned 
against  the  careless  use  of  any  of  these  sources 
of  light  while  unprotected  sensitive  plates  are 
around. 

During  the  various  operations  of  removing 
the  sensitive  plates  from  the  packing  box,  put- 
ting them  in  plate-holders  or  in  printing- 
frames,  and  in  the  manipulations  of  the  plates 
during  development  and  fixing,  the  plates 
should  be  carefully  protected  from  any  kind  of 
actinic  light,  because  they  are  very  sensitive  as 
compared  with  sensitized  paper. 

The  reader  must  get  the  above  warning 
firmly  fixed  in  the  mind,  for  it  will  save  much 
vexation  and  annoyance  later. 

The  effect  which  actinic  light  has  upon  the 
sensitive  plate  is  wholly  invisible,  unless  the 
exposure  is  continued  for  a long  period  of  time. 
For  example,  take  a plate,  put  it  in  a camera 
and  make  an  exposure  for  one  second,  then  ex- 
amine the  plate  carefully.  No  change  will  be 
visible.  That  a change  has  really  taken  place 
may  be  proved  by  pouring  upon  the  plate  a so- 
lution containing  certain  chemicals,  called  the 
developer. 

If  a plate  be  exposed  openly  to  daylight  for 
several  minutes  or  an  hour,  it  will  turn  a gray  or 
chocolate  color  ; no  chemicals  are  necessary  in 
this  case  to  show  that  a change  has  taken  place. 
Chemists  have  not  yet  explained  this  wonderful 
action  of  light. 


11 


Fortunately  the  explanation  is  not  essential 
so  long-  as  we  can  make  use  of  this  action,  de- 
tect it,  modify  and  extend  it,  until  we  obtain 
the  object  we  desire,  namely,  the  fixed  result 
of  the  unknown  chemical  action  of  light,  called 
the  image  on  the  plate.  This  is  done  by  a pro- 
cess consisting  of  two  steps  ; ist,  developing  the 
invisible  image  until  it  is  seen  ; 2d,  fixing  the 
image  so  that  it  will  remain  permanently  upon 
the  plate.  Let  us  return  to  the  experiments 
with  the  two  plates  exposed  to  actinic  light. 
The  first,  which  was  exposed  for  a short  time 
only,  needed  the  aid  of  powerful  chemical 
agents  to  bring  out  or  develop  the  image. 

The  second  needed  none  at  all. 

A logical  conclusion  may  be  drawn,  that  if, 
on  one  hand,  a plate  has  been  exposed  an  ex- 
ceedingly short  time  to  actinic  light,  the  chemi- 
cal agents  applied  to  bring  out  or  to  develop  the 
image  must  be  powerful  and  be  allowed  to  act 
upon  the  plate  for  a long  time  ; on  the  other 
hand,  a plate  exposed  for  a longer  period  re- 
quires less  powerful  agents  to  produce  the 
image.  Going  a step  further,  we  may  conclude 
that  a perfect  balance  may  be  obtained  between 
the  exposure  and  the  developing  agents,  so  that 
the  chemical  action  of  the  latter  will  develop 
the  invisible  image  produced  by  the  former  to 
a proper  degree,  and  no  more  or  less. 

When  this  balance  is  attained,  perfection  is 
the  result. 

While  this  is  theoretically  easy,  it  is  not  often 
attained  in  practice  on  account  of  the  many 


12 


variable  quantities  which  enter  into  the  calcu- 
lation. For  example,  daylight  varies  at  all 
times  of  the  day  and  the  year  ; therefore,  it  is  a 
very  uncertain  element  to  deal  with.  Almost 
any  source  of  steady,  unvarying  light  is  better 
for  our  purpose,  such  as  a kerosene  lamp,  a gas 
jet  or  the  electric  light.  The  temperature  of 
the  room  in  which  we  work  is  another  varying 
element,  and  especially  the  temperature  of 
the  developing  solution  itself,  which  should  be 
between  65  and  75  degrees  Fahr.  A slight 
variation  in  temperature  will  cause  a complete 
change  in  the  action  of  the  developer.  The  de- 
velopers, which  will  be  described  subsequently, 
must  be  warmed  or  cooled,  as  the  case  may  be, 
until  they  are  of  the  proper  temperature,  other- 
wise they  cannot  be  depended  upon  at  all. 

These  difficulties,  when  once  pointed  out, 
ought  never  to  trouble  a careful  worker. 

The  personal  element  now  steps  in,  and  this 
is  the  most  unreliable  quality  of  them  all.  It 
has  a habit  of  exhibiting  new  phases  every  day, 
and  often  leads  one  to  believe  in  the  doctrine  of 
the  total  depravity  of  things  in  general. 

De  gustibus  non  est  disputandnm ; therefore 
“ agree  to  disagree,”  if  necessary,  but  follow 
the  directions  closely. 


CHAPTER  I. 

The  Contact  Method. 


WO  methods  of  making  lantern  slides  will  be 


carefully  described.  The  first  will  be  called 
the  “contact  method,”  which  consists  in  print- 
ing on  prepared  sensitized  glass,  just  as  if  it 
were  paper.  It  is  done  by  placing  a negative 
in  an  ordinary  printing  frame,  and  then  adjust- 
ing the  gelatine  surface  of  a prepared  slide  plate 
directly  against  the  image  on  the  negative,  and 
keeping  it  in  firm  contact  with  the  latter  by 
means  of  the  springs  of  the  pressure  board  of 
the  printing  frame,  while  actinic  light  is  allowed 
to  shine  through  the  negative  upon  the  slide 
plate.  The  thicker  portions  of  the  negative 
stop  the  light  to  a certain  degree,  and,  therefore, 
there  is  little  or  no  chemical  action  upon  the 
corresponding  parts  of  the  slide  plate.  The 
thinner  portions  allow  more  light  to  pass ; 
therefore,  there  is  more  action  upon  the  corre- 
sponding parts  of  the  slide,  so  that  the  chemical 
action  of  the  light  upon  the  various  parts  of  the 
slide  plate  depends  upon  the  thickness  of  the 
respective  parts  of  the  negative.  Moreover,  it 
also  depends  upon  the  length  of  time  that  the 
light  acts  upon  the  plate. 

The  exposure  may  be  so  long  that  too  much 
action  takes  place,  even  under  the  thickest  parts 
of  the  negative,  so  that  the  delicate  gradations 


14 


of  action,  so  much,  desired,  are  completely  lost, 
and  the  picture  is  seen  through  a veil  of  haze 
called  “fog.”  Some  have  called  it  “atmos- 
phere.” Well,  the  atmosphere  is  sometimes 
“foggy  ”;  but  there  is  a difference  between  the 
natural  and  the  chemical. 

When  a plate  has  been  over-exposed — that  is, 
exposed  too  long  to  actinic  light — it  invariably 
begins  to  change  or  “come  up  ” as  soon  as  it  is 
thoroughly  wet  by  the  developer,  and  the  de- 
veloping action  is  often  so  rapid  that  no  amount 
of  manipulation  can  save  the  picture.  In  slide 
work  it  is  only  a matter  of  a few  moments  to 
make  another  and  a shorter  exposure  ; there- 
fore much  time  and  expense  are  really  saved  by 
refraining  from  tinkering  with  the  developer  or 
the  over-exposed  plate. 

If  it  were  a negative,  and  another  exposure 
were  impossible,  any  kind  of  dodging  would  be 
allowable,  but  it  is  “love’s  labor  lost  ” on  a slide. 
Then,  again,  the  exposure  may  not  be  long 
enough  for  a sufficient  amount  of  light  to  pass 
through  any  parts  of  the  negative  except  the 
very  thinnest.  This  is  called  under-exposure , 
and  is  much  worse  than  its  opposite.  In  this 
case  the  plate  will  lie  in  the  developer  for  a long 
time  before  any  change  whatever  is  seen,  and 
after  it  begins  it  will  proceed  so  slowly  that 
three  or  four  slides,  properly  exposed,  could  be 
made  and  developed  before  the  under-exposed 
one  is  nearly  so  ; and  even  when  this  state  does 
occur,  if  it  ever  does,  the  slide  had  better  be 
converted  into  a cover  glass  at  once,  otherwise 


15 


it  will  be  nothing-  but  a failure  in  “ black  and 
white.” 

The  author  is  unacquainted  with  any  method 
that  will  produce  a suitable  deposit  on  an  under- 
exposed plate,  either  a negative  or  a slide.  It  is 
trying  to  create,  and  that  is  impossible  without 
divine  power.  A slight  over-exposure  may 
often  be  restrained  by  plunging  the  developing 
plate  under  very  cold  water  and  leaving  it  there 
until  another  very  weak  and  cool  developer, 
containing  proportionately  a large  quantity  of 
potassium  bromide,  is  prepared  for  it.  This 
method  is  very  valuable  for  negatives,  but  is 
not  advised  for  slides,  because  a better  general 
average  will  result  from  the  use  of  one  standard 
developer,  unchanged  or  unmodified,  changing 
the  time  of  exposure  to  suit  the  negative  and  the 
developer.  There  are  enough  variable  quan- 
tities to  guard  against  without  adding  still 
another. 

Experience,  although  the  most  expensive,  is 
the  best  of  teachers  ; therefore  allow  it  to  lay 
down  the  following  digest  cf  twenty-one  years’ 
work. 

Use  : 

First. — A standard  negative. 

Second. — A standard  slide  plate  of  one  kind. 

Third. — A standard  actinic  lisfht. 

Fourth. — A standard  developer. 

And  change  none  of  these  invariables  in  the 
contest  with  the  variable  : 

(a)  Time  of  exposure. 

(i b ) Temperature. 


16 


(r)  Period  of  time  the  plate  is  in  the  developer. 
(d ) The  mental  state  of  yourself. 

Have  all  things  clean — darkroom,  apparatus, 
plates  and  solutions,  and  especially  your  hands. 

Don’t  be  in  a hurry  ; if  you  haven’t  time 
enough  to  make  a good  slide,  it  is  better  not  to 
make  any. 

Requisites  for  the  “Contact  Method.” 

1.  A controllable  source  of  actinic  light. 

2.  A means  of  measuring  the  time  of  ex- 

posure. 

3.  A lamp  which  yields  non-actinic  light. 

4.  Lantern  slide  plates. 

5.  A printing  frame. 

6.  Trays  for  the  various  operations. 

7.  A camel’s-hair  duster. 

8.  A measuring  glass,  or  graduate. 

9.  A glass  funnel. 

10.  Absorbent  cotton. 

11.  A means  of  washing  the  plates. 

12.  A plate  rack. 

13.  A i-inch  flat  camel’s-hair  brush  for  the  red 

prussiate  of  potash  solution. 

14.  Lantern-slide  mats. 

15.  Gummed  strip  of  paper  for  binding  the 

finished  slides. 

Chemicals  Required. 

1.  Developer. 

2.  Potassium  bromide. 

3.  A bottle  of  acid  sulphite  of  soda. 


17 


Hyposulphite  of  soda. 

5.  Powdered  alum. 

6.  Red  prussiate  of  potash. 

All  of  these  articles  may  be  obtained  from  the 
publishers,  and  all  except  the  developer  may  be 
obtained  anywhere.  Formulas  for  developers 
will  be  given  later. 

Each  article  will  now  be  described  in  detail. 

1.  The  most  convenient  source  of  actinic 
light  is  the  incandescent  electric  lamp,  which 
can  be  turned  on  and  off,  at  pleasure. 


Next  in  value  is  a gas-jet,  controlled  by  a 
ratchet  device  and  lighted  by  an  electric  spark. 
One  pull  of  the  pendant  chain  turns  on  the  gas 
and  lights  it  at  the  same  time. 

A second  pull  shuts  off  the  gas,  and,  of  course, 
extinguishes  the  light. 


18 


This  apparatus,  while  it  is  admirably  adapted 
to  the  purpose  of  exposing-  slides,  is  rather  ex- 
pensive; for,  in  addition  to  the  jet  itself,  which 
costs  $1.25,  a spark  coil  ($3)  and  a battery  of 
three  or  four  cells  (50  cents  per  cell),  are  neces- 
sary. The  most  convenient  battery  is  the 
“ dry  ” form  of  cell.  The  whole  apparatus  costs 
about  $6.  This  is  the  form  of  actinic  light  used 
by  the  author,  and  it  leaves  nothing  to  be  de- 
sired. Any  length  of  exposure  may  be  obtained 
with  the  utmost  ease.  It  has  never  failed;  and 
when  the  gas  is  turned  off,  the  light  is  entirely 
extinguished. 

Another  form  of  jet,  while  not  equal  to  the 
first  in  every  respect,  is  quite  well  adapted  to 
the  purpose. 

It  is  a gas-jet  with  a “ by-pass,”  screwed  upon 
a small  iron  stand,  which  may  be  connected 
with  any  gas  fixture  by  means  of  rubber 
tubing. 

The  flow  of  gas  is  controlled  by  a stop-cock, 
which  is  connected  with  a very  small  “ by-pass  ” 
tube  at  one  side.  The  gas  is  first  turned  on  and 
lighted  as  an  ordinary  jet. 

As  the  stop-cock  is  turned,  it  opens  the  by- 
pass tube  so  that  a very  small  flow  of  gas 
escapes  at  the  orifice  and  is  lighted  by  the 
main  flame  just  before  the  latter  is  extinguished. 
This  little  by-pass  jet  continues  to  burn  as  long 
as  the  main  jet  is  turned  off. 

When  the  main  jet  is  gradually  turned  on,  it 
is  lighted  by  the  small  jet,  which  is  completely 
extinguished  when  the  main  jet  is  full  on. 


19 


There  are  two  slight  objections  to  this 
burner: 

In  the  first  place,  the  by-pass  flame,  although 
small,  gives  off  some  actinic  light;  therefore  it 
is  best  to  keep  the  burner  at  some  distance 
from  the  developing  table. 

Secondly,  it  is  liable  to  go  out  entirely  if  the 
stop-cock  is  turned  with  a sudden  jerk.  It  is 
also  liable  to  be  blown  out  by  the  slightest 
down  draft.  If  gas  is  not  within  reach,  a 
kerosene  lamp  will  answer,  if  it  is  placed  in  a 
light-tight,  not  air-tight,  box,  having  a swinging 
door  which  may  be  easily  opened  and  closed. 

The  author  does  not  believe  in  “ make-shifts  ” 
of  any  kind. 

As  a last  resort,  the  lamp  used  for  developing 
may  be  arranged  with  a swinging  door,  so  that 
one  source  of  light  may  serve  the  two  purposes; 
but  it  is  preferable  to  leave  the  developing  lamp 
undisturbed. 

2.  The  simplest  and  most  convenient  method 
of  measuring  the  exposure  of  actinic  light  is  by 
means  of  an  ordinary  cheap  metallic  clock, 
which  has  a good,  loud  tick  that  may  be  easily 
heard  all  over  the  darkroom.  The  author  uses 
a 79-cent  clock,  which  ticks  four  times  to  the 
second.  It  is  placed  on  a shelf  directly  under 
the  exposure  gas-jet  and  measures  off  quarter, 
half  or  full  seconds  with  unchanging  accuracy, 
without  requiring  much  mental  strain  on  the 
part  of  the  operator.  The  tick  of  the  clock  will 
enable  one  to  repeat  an  exact  exposure  on  any 
number  of  plates. 


20 


It  is  a very  bad  plan  to  trust  to  one’s  own 
sense  of  time  in  exposing  lantern  slides. 

3.  A good  lamp  for  the  developing  table  is  an 
absolute  necessity.  A small  one  is  an  abomina- 
tion for  slide  work.  One  of  the  best  on  the 
market  is  Carbutt’s  “ Multum  in  Parvo,”  which 
can  be  very  much  improved  by  removing  all 
the  glass  it  contains  and  substituting  ruby  glass 
at  the  sides  and  an  8 x 10  “dark  amber  ” glass 
in  front,  which  should  be  backed  by  a piece  of 
plain  ground-glass  of  the  same  dimensions. 


The  addition  of  the  ground-glass  will  surprise 
those  who  have  never  tried  it,  as  it  gives  a 
diffused  light  that  is  delightful  to  work  by. 
The  slightest  change  in  the  plate  can  be  de- 
tected at  once,  and,  moreover,  more  light  can 
be  used  without  danger  of  fogging  the  plates 
than  is  possible  without  the  ground-glass. 

Instead  of  the  kerosene  lamp  a gas  burner 
upon  a small  stand  which  is  connected  with  a 
gas  pipe  is  used.  A controlling  stop-cock  is 


21 


placed  outside  of  the  lantern  so  that  the  light 
may  be  increased  or  diminished  at  pleasure 
without  opening  the  lamp. 

4.  F or  slide  plates  the  author  prefers  Carbutt’s 
and  Cramer’s. 

5.  One  or  two  printing  frames  with  the 
pressure  board  backed  with  black  broadcloth 
which  does  not  fray  easily. 

6.  Four  trays  are  required,  two  large  enough 
to  hold  two  35x4  plates  conveniently.  These 
are  to  be  used  for  developing  only. 


Improved  Printing  Frame. 

Deep  white  porcelain  trays  are  recommended 
because  they  form  a good  contrast  to  the  plate  as 
it  develops,  and  they  show  dirt  when  there  is  any. 

A third  one,  large  enough  to  hold  four  slide 
plates,  is  used  for  the  hyposulphite  of  soda  solu- 
tion only;  and  the  fourth,  a tray  of  equal  size, 
for  the  alum  solution  only.  These  trays  should 
be  used  for  the  purposes  indicated,  respectively, 
and  for  nothing  else. 


22 


To  avoid  the  misuse  of  a tray,  it  is  a good 
plan  to  mark  each  one.  The  gold  paint  liquid 
sold  in  all  paint  shops  answers  this  purpose  bet- 
ter than  anything  else.  It  resists  the  action  of 
photographic  chemicals  for  a long  time  and  is 
plainly  visible  in  ruby  or  amber  light. 

7.  A good  camel’s-hair  duster  is  a sine  qua  non. 
It  should  be  at  least  2 inches  wide. 

It  must  be  washed  first  with  soap  and  water 
and  then  with  a little  soda  and  water,  after 
which  it  should  be 
held  under  the  tap 
until  all  soap  and  soda 
have  been  washed 
out;  then  partially 
dried  with  a clean 
towel  and  hung  up  to 
dry  spontaneously  in 
some  place  free  from 
dust. 

The  fingers  should 
never  come  in  contact 
with  this  brush.  A 
duster  which  has 
been  in  contact  with 
the  human  skin  will 
leave  upon  the  plate 

that  which  is  much  Graduate. 

worse  than  dust.  In  this  connection  remember 
that  a finger  mark  upon  a slide  is  not  a beauty 
spot,  even  if  made  by  a pretty  finger. 

8.  A measuring-glass  or  graduate — an  8-ounce 
one  will  answer.  The  ordinary  thick  precipi- 


23 


fating  jars  are  just  the  thing  for  holding  devel- 
opers in  use,  as  the  liquid  may  be  decanted, 
leaving  the  particles  of  dirt  and  gelatine  upon 
the  bottom. 

They  do  away  with  the  necessity  of  filtering 
the  developer  frequently. 

9.  One  or  two  quart  glass  funnels,  to  be  used 
with  paper  or  absorbent  cotton,  as  filters. 

10.  Absorbent  cotton  is  very  useful  as  a filter, 
and  for  swabs  for  swabbing  of  plates,  as  will  be 
described. 


11.  A good  wash-box  for  thoroughly  washing 
the  plates  after  they  have  been  fixed.  The  per- 
manency of  the  slide  depends  partly  upon  the 
thoroughness  of  the  final  washing. 

12.  A rack  for  holding  the  plates  while  they 
are  drying  spontaneously. 

13.  The  use  of  the  small  camel’s-hair  brush 
will  be  described  in  its  proper  place. 

14.  Lantern-slide  mats  are  pieces  of  black 


24 


paper  3 J x 4 inches,  with  an  opening  cut  out  of 
the  center.  The  openings  are  of  various  shapes. 

15.  For  gummed  paper  the  author  uses  Sheplie 
gum  paper,  which  works  better  than  anything 
else  on  the  market,  and,  being  of  a light  color, 
the  name  of  the  slide  can  be  written  upon  it. 

Chemicals  and  Preparations  Required. 

1.  Developer.  A bottle  of  Anthony’s  improved 
Hydroquinone  developer,  which  comes  prepared 
in  8 and  16-ounce  bottles. 


Drying  Rack. 

This  developer  is  an  admirable  one  for  slides. 
It  is  clean,  does  not  stain  the  fingers  much,  has 
wonderful  keeping  qualities,  and  will  make  as 
fine  a slide  as  any  developer  the  author  is 
acquainted  with. 

Tom,  Dick  or  Harry  may  have  just  as  good  a 
one,  but  the  following  directions  are  based  upon 
this  developer  and  upon  the  Carbutt  or  Cramer 
plates,  and  the  author  will  shuffle  off  any  and 
all  responsibility  if  any  others  are  used.  No 
one  can  make  a perfect  negative  or  a perfect 
slide  every  time,  so  don’t  expect  to. 


THE  LANTERNIST’S  DARKROOM. 


I 


25 


At  the  close,  formulas  will  be  given  for  those 
who  desire  to  work  out  their  own  salvation. 

2.  An  ounce  bottle  of  potassium  bromide. 
Take  an  empty  ounce  bottle,  fill  one-fourth  of 
it  with  bromide  crystals  and  then  fill  up  with 
water.  Shake  it  thoroughly;  if  all  the  crystals 
dissolve,  put  in  some  more  and  shake  again.  In 
a short  time  one  can  be  satisfied  that  no  more 
crystals  will  dissolve.  When  this  state  of  affairs 
is  reached,  the  solution  is  said  to  be  “ saturated.” 
And  a saturated  solution  of  the  bromide  is  what 
is  wanted.  Mark  the  bottle  “ bromide  solution.” 
It  is  used  in  connection  with  the  developer. 

3.  The  acid  sulphite  of  soda  is  used  in  con- 
nection with  hyposulphite  of  soda. 

4.  A solution  of  hyposulphite  of  soda,  com- 
monly called  “hypo,”  or  the  fixing  solution. 

Take  8 ounces  of  hypo,  put  it  in  32  ounces  of 
water  and  shake  until  the  crystals  are  dissolved, 
then  add  half  a drachm  of  the  acid  sulphite  of 
soda.  Mark  this  bottle  “hypo  solution.” 

The  acid  sulphite  keeps  the  hypo  solution 
clear,  so  that  there  is  no  danger  of  staining  the 
plates.  A very  small  quantity  is  sufficient,  too 
much  is  an  evil.  Hypo  is  very  cheap,  so  don’t 
work  it  to  death.  A fresh  solution  should  be 
made  every  day  or  two  if  many  plates  are  fixed, 
and  a fresh  solution  is  always  safer  even  if  only 
a few  plates  are  to  be  fixed.  Never  use  it  if  the 
solution  is  yellow  or  brown. 

5 . Put  powdered  alum  into  a pint  bottle  of  water 
until  no  more  will  dissolve  and  some  undissolved 
powder  remains  on  the  bottom  of  the  bottle. 


26 


This  forms  a saturated  solution  of  alum  which 
must  be  filtered  before  it  is  used.  It  hardens 
the  gelatine  and  prepares  it  for  future  applica- 
tions of  color. 

6.  The  red  prussiate  of  potash  is  very  poison- 
ous and  should  be  handled  with  care.  Its  use 
will  be  indicated  in  an  appropriate  place. 

Before  beginning  to  make  lantern  slides  be 
sure  that  the  darkroom  is  quite  clean,  especially 
the  developing  table  and  the  floor  under  and 
around  it.  It  is  the  invariable  custom  of  the 
author  to  wipe  the  table  and  floor  with  a damp 
cloth. 

This  precaution  is  always  necessary,  but  par- 
ticularly so  if  the  room  has  been  used  for 
developing  purposes  previously.  It  is  almost 
impossible  to  prevent  some  of  the  various  solu- 
tions from  dropping  from  the  plates  or  fingers 
during  the  processes  of  development  and  fixing, 
and  as  the  water  soon  evaporates,  fine  crystalline 
deposits  are  left,  which  ascend  in  the  form  of 
fine  dust  upon  the  slightest  provocation. 

This  chemical  dust  has  disastrous  effects  upon 
every  photographic  article  it  touches.  It  is 
worse  than  any  form  of  bacilli,  because  there 
are  no  remedies  for  the  evils  it  causes.  A strict 
quarantine  against  the  plague  is  the  only  safe- 
guard. 

Be  sure  that  the  source  of  actinic  light  and 
the  developing  lantern  are  in  order.  Fill  the 
hypo  tray  half  full  of  filtered  hypo  solution,  and 
into  the  alum  tray  pour  an  equal  quantity  of 
filtered  alum  solution.  Keep  these  trays  away 


27 


from  the  developing  table  at  all  times  with  great 
care. 

Measure  out  3 ounces  of  Anthony’s  hydro- 
quinone  developer,  as  it  comes  prepared  in 
bottles,  and  add  2 ounces  of  pure  water.  Croton 
water  is  liable  to  turn  it  yellow  very  quickly. 
Then  add  two  or  three  drops  of  the  bromide 
solution.  This  mixture  forms  the  standard 
developer.  N ever  allow  anything  else  but  plates 
to  get  into  this  developer. 

Clean  the  back  (the  glass  side)  of  the  standard 
negative,  dust  off  the  gelatine  surface  with  a 
camel’s-hair  duster,  and  place  it  in  a printing 
frame,  gelatine  side  up. 

All  the  foregoing  operations  should  be  carried 
on  by  ordinary  light. 

At  this  point  all  actinic  light  of  any  kind 
should  be  shut  off  ; of  course  no  stray  rays  of 
daylight  should  be  admitted  into  the  darkroom. 

By  the  red  or  amber  light  of  the  developing 
lantern  open  a box  of  slide  plates,  dust  off  both 
sides  of  one,  being  careful  to  dust  the  gelatine 
side  last,  and  place  it  upon  the  negative  in  the 
printing  frame,  so  that  the  creamy  white  gelatine 
surface  of  the  plate  is  in  contact  with  the 
negative.  Then  take  up  the  frame,  holding  the 
plates  in  contact  gently  with  the  thumbs,  and 
adjust  the  slide  plate  over  the  desirable  part  of 
the  negative,  while  looking  through  the  plates 
at  the  developing  light.  When  the  desired 
position  is  obtained,  lay  the  frame  down  level 
and  adjust  the  pressure  board  carefully,  so  as 
not  to  move  the  slide  plate.  U nless  this  is  care- 


28 


fully  done,  the  negative  may  be  scratched  or 
broken. 

Put  away,  or  close,  the  opened  box  of  plates. 

The  plate  is  now  ready  for  exposure  to  actinic 
light. 

Hold  the  frame  so  that  the  light,  when  turned 
on,  may  fall  perpendicularly  upon  the  negative 
at  a measured  distance  from  the  source  of  the 
light,  say,  2 feet. 

These  two  points  must  be  carefully  noted,  for, 
in  the  first  place,  the  sharpness  or  distinctness 
of  the  image  depends  upon  the  direction  in 
which  the  light  passes  through  the  negative. 
When  the  rays  pass  through  it  perpendicular 
(at  right  angles)  to  its  surface,  the  sharpest 
image  is  obtained. 

In  the  second  place  the  negative  should  be  at 
a known  distance  from  the  source  of  light, 
because  the  intensity  or  active  power  of  light 
varies  inversely  as  the  square  of  the  distance 
from  its  source.  That  is,  if  the  negative,  at  a 
distance  of  2 feet  from  the  light,  requires  an 
exposure  of  four  seconds,  at  one-half  of  the  dis- 
tance, 1 foot,  it  would  require  an  exposure  of 
only  one  second  to  obtain  the  same  result.  At 
twice  the  distance,  4 feet,  it  would  require  an 
exposure  of  sixteen  seconds.  Therefore  be 
careful  about  these  little  things,  or  there  will 
be  variations  in  the  results  of  the  exposures, 
even  when  exactly  timed. 

To  return  to  the  work  : 

Hold  the  frame  as  directed  and  turn  on  the 
actinic  light  for  two  seconds  by  the  clock.  Re- 


29 


move  the  slide  plate  and  write  plainly,  “ two 
seconds,”  across  the  gelatine  surface  with  a lead 
pencil.  Put  this  plate  away,  or  wrap  it  up  light- 
tight for  a few  moments. 

Adjust  another  slide  plate  on  the  same  nega- 
tive, and  under  the  same  conditions  exactly 
expose  it  four  seconds.  Remove  this  plate  from 
the  frame,  mark  it  “ four  seconds,”  and  place  it 
with  the  other  exposed  plate. 

After  testing  the  temperature  of  the  devel- 
oper, which  should  he  about  70  degrees  Fahr., 
pour  it  into  a clean  developing  tray.  The 
temperature  should  not  be  lower  than  65  de- 
grees nor  higher  than  75  degrees.  A cold 
developer  works  too  slowly  and  makes  the  plates 
black  and  white,  while  a warm  one  is  too  rapid 
in  its  action  and  causes  a smoky  appearance. 
It  is  better  to  have  it  just  right. 

The  tray  should  be  placed  in  front  of,  and 
about  6 inches  from,  the  amber  glass  of  the 
developing  lantern. 

Place  the  two  exposed  plates,  gelatine  side  up, 
in  the  developer,  and  rock  the  tray  back  and 
forth  so  that  the  developer  rushes  over  the  plates 
in  every  direction.  There  must  be  enough  de- 
veloper in  the  tray  to  cover  the  plates  to  a depth 
of  at  least  an  eighth  of  an  inch  when  the  tray  is 
level.  Plenty  of  developer  must  be  the  rule. 

The  rocking  motion  must  be  kept  up  during 
the  greater  part  of  the  time  the  plates  are  in  the 
developer.  Without  this  motion  the  plates  de- 
velop unevenly,  and  are  liable  to  be  spotted 
or  mottled,  and  will  often  appear  like  some  of 


30 


the  half-tone  prints  sometimes  seen  in  maga- 
zines, which  are  wretched  apologies,  to  put  it 
mildly. 

The  plate  marked  “ four  seconds  ” will  pro- 
bably begin  to  change  color  slightly  in  about 
thirty  or  forty  seconds.  It  may  begin  sooner. 
At  all  events  it  will  begin  before  that  marked 
“two  seconds.”  The  exact  time  to  elapse  be- 
fore the  action  begins  cannot  be  predicted  by 
one  unacquainted  with  the  negative  or  slide 
plate  used.  Different  emulsions,  even  by  the 
same  manufacturer,  vary  greatly  in  sensitive- 
ness, no  matter  how  they  are  marked.  Don’t 
get  impatient,  but  keep  on  rocking  the  tray. 
If  the  outlines  of  the  picture  are  not  distinctly 
seen  after  sixty  or  a hundred  seconds  have 
elapsed,  the  indications  are  that  the  plates  were 
not  exposed  long  enough.  If,  however,  one  of 
them  does  come  up  nicely,  the  correct  exposure 
may  have  been  found  in  this  first  attempt,  or  it 
may  be  between  two  and  four  seconds.  If  they 
do  not  develop  nicely,  cover  the  tray  with  the 
top  of  a cardboard  box  to  exclude  light,  leaving 
the  plates  in  the  developer,  and  expose  another 
plate  on  the  same  negative,  under  the  same 
conditions,  five  seconds  exactly.  Mark  it  and 
put  it  away.  Then  expose  still  another  on  the 
same  negative,  as  before,  six  seconds.  Mark 
this  and  put  it  with  the  five-second  plate. 

Remove  the  first  two  plates  from  the  devel- 
oper, rinse  them  off  by  holding  them  under  a 
tap  for  a moment,  and  then  put  them  into  the 
hypo  solution.  Don’t  put  your  fingers  into  the 


31 


hypo.  If  the  fingers  are  wet  with  hypo  they 
should  be  thoroughly  washed  before  any  other 
work  with  plates  or  developer  is  attempted. 

Put  the  last  two  exposed  plates  into  the  de- 
veloper, and  rock  the  tray  as  before.  Probably 
one  of  these  plates  has  been  correctly  exposed, 
so  watch  closely.  The  plate  which  had  the 
longer  exposure  will  begin  to  change  color 
first.  In  a few  moments  after  the  plates  are 
thoroughly  wet  by  the  developer,  the  outlines 
of  the  picture  will  begin  to  appear,  somewhat 
as  they  do  on  sensitive  paper  in  sunlight,  only 
the  color  will  be  different,  either  brown  or  black  ; 
and  every  little  detail  will  gradually  be  seen  in- 
creasing in  distinctness  and  in  depth  of  color, 
until  it  appears  as  a finished  photograph,  but 
more  beautiful. 

The  plate  which  had  five  seconds  exposure 
will  “ come  up  ” or  develop  somewhat  slower, 
but  that  is  only  to  be  expected  because  it  was 
exposed  a shorter  time  to  the  actinic  light. 
When  the  former  plate  looks  quite  dark,  the 
latter  will  appear  lighter.  Note  carefully  the 
degree  of  darkness  of  each  plate  as  compared 
with  the  white  bottom  of  the  tray. 

When  the  six-second  plate  has  become  much 
darker  than  you  think  it  ought  to  be,  take  both 
plates  out  of  the  developer,  rinse  them  off  under 
the  tap  and  place  them  in  the  hypo  and  leave 
them  there  for  two  or  three  minutes.  Put  away 
all  the  unexposed  plates  and  turn  on  the  actinic 
light. 

Then  take  the  first  two  plates  out  of  the  hypo, 


32 


rinse  them  off,  and  hold  them  up  between  the 
light  and  the  eyes,  placing  a piece  of  ground 
glass  between  the  plates  and  the  light.  Examine 
them  carefully,  by  looking  through  them  at  the 
ground-glass.  The  plate  exposed  two  seconds 
probably  will  have  little  or  nothing  upon  it. 

That  exposed  four  seconds  may  have  quite  a 
good  image,  but  very  cold  or  black  and  white, 
and  it  may  be  very  thin.  Then  take  out  the 
last  two  plates,  rinse  them  off,  and  examine 
them  by  looking  through  them  at  the  brightly 
illuminated  ground-glass.  The  novice  will  prob- 
ably be  surprised  to  find  all  of  the  plates  much 
thinner  than  when  they  were  placed  in  the 
hypo.  A short  description  of  the  cause  of  this 
may  be  of  benefit. 

The  actinic  light  forms  the  invisible  image, 
the  developer  causes  a chemical  reaction  upon 
the  molecules  of  silver  which  have  been  acted 
upon  by  the  light,  so  that  the  image  not  only 
becomes  visible,  it  also  becomes  a body  as  we 
understand  the  term. 

The  developer  seems  to  pile  up  the  molecules 
of  silver  upon  the  plate  so  that  where  there  was 
the  greatest  action  of  light  there  is  the  greatest 
depth  of  deposit  and  vice  versa.  When  the 
conditions  are  favorable,  this  is  one  of  the  most 
beautiful  of  all  chemical  actions. 

As  all  of  the  molecules  of  silver  upon  the 
plate  are  not  acted  upon  by  the  light  when  the 
exposure  is  correct,  it  is  necessary  to  remove  all 
those  not  developed,  and  the  hypo  does  this  ; it 
is  called  fixing.  The  greater  part  of  the  silver 


33 


on  a plate  is  dissolved  in  the  hypo,  therefore  the 
plate  is  much  thinner  when  it  leaves  it.  For 
this  reason  the  plates  must  be  developed  much 
darker  or  thicker  than  at  first  seems  necessary. 
The  development  must  be  kept  on  long-  after 
the  picture  looks  very  nice.  The  most  difficult 
point  in  the  whole  process  is  the  determination 
of  the  exact  amount  of  deposit  developed  upon 
the  plate. 

In  other  words  it  is  difficult  to  decide  upon 
the  exact  moment  to  remove  the  plates  from 
the  developer.  This  desirable  knowledge  can 
only  be  attained  by  systematic  experiments  with 
one  negative,  one  developer  and  one  kind  of 
plate,  a tentative  method  which  trains  the  eyes 
to  a nice  perception  of  detail  and  density  or 
thickness  of  deposit. 

Returning  to  the  four  developed  and  fixed 
plates,  choose  the  best  one  and  note  the  time  of 
exposure  written  upon  it. 

Suppose,  for  example,  it  was  five  seconds. 
Expose  two  more  slide  plates  on  the  same  nega- 
tive, giving  each  plate  exactly  five  seconds  at 
the  same  distance  from  the  light,  that  is,  under 
the  same  conditions  as  before.  Put  these  plates 
into  the  same  developer.  Having  an  equal  ex- 
posure they  will  develop  alike.  Develop  them 
until  they  seem  to  be  dark  enough.  Then 
remove  one  of  them,  rinse  it  and  place  it  in  the 
hypo,  leaving  the  other  in  the  developer  a little 
longer,  say  ten  or  twenty  seconds.  Then  re- 
move it,  rinse  it,  and  place  it  in  the  hypo,  so 
that  it  can  be  easily  distinguished  from  the 


34 


other.  After  a lapse  of  two  or  three  minutes 
they  will  be  fixed  enough  for  examination. 

Compare  them  before  the  ground-glass  and 
white  light.  Which  is  the  better  ? 

If  it  is  the  one  removed  last  from  the  de- 
veloper, be  careful  to  develop  other  slides  a 
little  longer  than  is  thought  necessary. 

If  it  was  that  removed  first,  try  to  imitate  in 
every  respect  the  manipulations  which  produced 
it.  If  they  are  both  too  dark,  they  were  de- 
veloped too  long.  Expose  two  more  plates  the 
same  length  of  time  the  best  slide  had,  and 
develop  them.  When  they  seem  to  be  devel- 
oped almost  enough,  take  one  plate  out,  rinse  it 
under  the  tap  for  a moment  and  examine  it  by 
looking  through  it  at  the  developing  light  for  a 
moment.  Study  its  qualities  carefully  by  trans- 
mitted light.  If  the  picture  is  a landscape,  the 
trees  and  all  shadows  should  appear  very  dark; 
the  sky  should  show  almost  nothing  at  all. 
After  noticing  everything  that  is  noticeable,  the 
slide  should  be  rinsed  and  placed  in  the  hypo. 
This  examination  should  not  last  over  ten 
seconds.  All  this  time  the  other  plate  is  devel- 
oping. Notice  its  appearance  in  the  developer; 
remove  it  when  it  seems  dark  enough;  rinse  it 
and  examine  it  also  by  transmitted  light,  taking 
care  to  notice  all  the  points  wherein  it  differs 
from  the  first  one.  After  a careful  examination, 
rinse  it  and  place  it  in  the  hypo,  keeping  it  apart 
from  the  other  plate.  It  is  easier  for  some  to 
judge  the  density  and  quality  of  a plate  by  trans- 
mitted than  by  reflected  light.  After  the  plates 


35 


are  fixed  they  may  be  examined,  and  the  good 
and  bad  points  of  each  carefully  noted. 

The  above  exposures  were  actually  tried  by 
a beginner,  working  under  the  author’s  direc- 
tions, and  the  results  were  very  gratifying  to 
both  pupil  and  instructor.  The  standard  nega- 
tive was  known,  and  the  series  of  exposures  was 
arranged  so  that  it  would  include  the  proper 
one,  but  the  pupil  was  not  aware  of  that  fact. 
The  pupil  decided  upon  the  correct  exposure 
without  any  suggestions  from  his  teacher. 

If  none  of  these  exposures  chance  to  be  the 
right  one  for  the  reader’s  standard  negative, 
other  periods  of  exposure  should  be  systematic- 
ally tried  after  the  same  manner.  After  a few 
trials  the  correct  exposure  will  be  found. 

This  tentative  method  may  seem  to  be  a waste 
of  plates  on  one  negative,  but  it  is  not,  even  if 
thirty  or  forty  plates  are  so  used.  Don’t  be  dis- 
couraged by  a few  or  by  many  failures.  The 
most  expert  slide-makers  don’t  obtain  twelve 
fine  slides  from  a dozen  plates — not  by  a large 
majority. 

By  thoughtfully  working  this  method  out  the 
novice  will  learn  how  to  judge  the  quality  of  the 
slide  as  it  develops,  and  when  to  remove  it  from 
the  developer. 

The  principal  idea  of  this  method  is  to  train 
the  eyes  so  that  the  moment  another  negative 
is  compared  with  the  standard  the  proper  ex- 
posure can  be  decided  upon  with  a certainty 
that  would  astonish  those  accustomed  to  modify 
their  developer  to  suit  any  haphazard  exposure. 


36 


Therefore,  keep  at  the  standard  negative  until 
not  only  one,  but  several  good  slides  are  made 
from  it,  without  modifying  the  developer  at  all. 
After  being  satisfied  that  a good  slide  can  be 
made  from  the  standard  negative,  mark  the  cor- 
rect exposure  upon  one  edge  of  the  negative. 
Then  compare  all  other  negatives,  from  which 
slides  are  to  be  made,  with  the  standard. 
Choose  those  which  are  of  the  same  density 
and  color,  and  place  them  in  one  pile.  They 
will  all  need  an  exposure  like  that  given  to  the 
standard.  Those  which  are  thicker  or  denser 
will  require  longer  exposures;  those  which  are 
thinner,  shorter. 

The  color  of  the  negative  also  necessitates  a 
change  in  the  length  of  exposure.  Those  which 
are  gray  require  less  than  those  which  are 
black.  Those  which  are  yellowish  require  very 
long  exposures. 

It  is  only  necessary  to  remember  what  was  said 
in  the  introduction  about  the  spectrum  colors  to 
see  the  logic  of  this. 

After  several  plates  (fifteen  or  twenty)  have 
been  developed  in  this  one  tray  of  developer,  its 
action  will  be  somewhat  weakened  and  there- 
fore slower.  It  is  then  advisable  to  throw  away 
half  of  it,  filter  the  remainder  and  add  to  it  an 
equal  quantity  of  new  developer  made  up  as 
directed  in  the  first  instance,  omitting  the  bro- 
mide solution. 

By  renewing  the  energy  of  the  developer  in 
this  way,  a constant  and  even  action  may  be 
kept  up  for  hours.  Never  employ  a developer 


D.  L.  Elmendorf. 


SIMPLON  ROAD,  ITALY. 


37 


which  has  once  been  used  after  it  has  stood  for 
one  or  two  days.  The  author  has  tried  it  and  it 
made  wretched  slides. 

Using  fresh  developer  is  like  using  a boiler 
having  a steam  gauge  upon  it — the  pressure  is 
known;  while  old  developer  is  like  an  old  gun 
that  has  been  loaded  for  years,  it  may  not  go  off 
at  all,  or  it  may,  and  take  the  immediate  neigh- 
borhood with  it,  “ there’s  no  tellin’.” 

After  the  plates  have  been  developed  they 
should  be  left  in  the  hypo  at  least  five  minutes  ; 
a longer  time  is  safer.  If  a plate  is  removed 
from  the  hypo  about  a minute  after  it  is  placed 
therein  and  examined  by  looking  at  the  back  of 
it,  the  edges  will  appear  dark,  while  the  center  is 
still  white. 

If  the  plate  is  dipped  in  and  out  of  the  hypo, 
the  dissolving  action  of  the  chemical  may  be 
watched.  Gradually  the  whole  plate  becomes 
dark  and  all  of  the  white  visible  silver  unacted 
upon  by  the  light  and  developer  seems  to  have 
been  removed,  but  this  is  not  so. 

This  action  goes  on  long  after  the  eyes  can 
distinguish  it ; therefore  it  is  necessary  that  the 
plate  should  remain  in  the  fixing  solution  until 
it  is  thoroughly  fixed.  This  is  essential  if  the 
slides  are  to  be  permanent.  If  they  are  not 
thoroughly  fixed,  they  soon  fade  and  turn  yellow. 
Actinic  light  should  not  strike  the  plates  while 
fixing.  After  the  plates  are  fixed  they  should 
be  thoroughly  washed  in  running  water  for  at 
least  two  or  three  minutes  and  then  while  under 
the  tap  swabbed  off  with  a wet  tuft  of  absorbent 


38 


cotton  and  then  placed  in  the  alum  bath. 
They  should  remain  in  this  from  two  to  five 
minutes.  The  exact  time  is  immaterial. 

The  alum  hardens  the  films  so  that  they  are 
not  liable  to  leave  the  glass.  The  alum  bath, 
moreover,  is  necessary  if  the  slides  are  to  be 
colored  afterwards.  After  the  alum  has  hard- 
ened the  film,  each  plate  should  be  placed  under 
the  tap,  swabbed  off  with  another  tuft  of  cotton 
again,  and  then  placed  in  the  wash  box  and 
washed  with  cool  running  water  for  at  least  half 
an  hour.  If  the  hypo  is  not  thoroughly  washed 
out,  it  will  stain  the  plate.  It  sometimes  crystal- 
lizes in  the  plate  long  after  the  slide  was  made 
and  ruins  it. 

After  a thorough  washing,  each  plate  should 
be  placed  under  a tap,  swabbed  off  with  cotton 
again,  and  then  placed  in  a plate  rack  and 
allowed  to  dry  spontaneously.  The  author  uses 
a small  electric  fan  which  dries  the  slides  in 
about  half  an  hour. 

When  dry  the  slide  may  oe  mounted  at  once, 
by  placing  a lantern-slide  mat  directly  upon  the 
gelatine.  By  moistening  one  corner  of  the  mat 
with  the  tongue  and  pressing  it  quickly  and  firmly 
upon  the  gelatine,  it  will  adhere  firmly  so  that  it 
retains  its  position.  Then  a clean  cover  glass  is 
laid  on  top  of  the  mat  and  the  two  glasses  are 
bound  together  with  gummed  strips  of  paper. 

The  cover  glass  protects  the  picture  from 
being  scratched,  the  mat  between  the  glasses 
acts  as  a buffer,  and  slides  well  mounted  may 
be  quite  roughly  handled  with  impunity. 


39 


If  the  slides  are  to  be  colored  they  must  not 
be  mounted  until  afterwards. 

Sometimes  a reproduction  of  printed  matter 
or  of  a line  drawing  is  required. 

The  negatives  of  such  subjects  should  be 
intense,  but  clear.  Negatives  which  are  very 
thick  and  black  are  often  called  intense  when 
not  so  at  all.  A very  poor  flat  image  is  mas- 
querading under  cover  of  a thick  mass  of  fog — 
that’s  all. 

Clearness  is  an  essential  for  line  work.  The 
lines  or  printed  matter  should  appear  as  clear 
glass  on  the  negative. 

After  adjusting  a slide  plate  on  the  negative, 
it  should  be  exposed  a very  short  time,  say,  one 
second  or  even  a half  second;  this,  of  course, 
depends  upon  the  clearness  of  the  negative. 

The  exposed  plate  should  be  developed  with 
Anthony’s  hydroquinone  developer  without  dilu- 
tion, adding  one  or  two  drops  of  the  bromide 
solution  to  3 ounces  of  developer.  The  develop- 
ment should  be  carried  on  till  the  lines  or  letters 
appear  very  black  and  the  whites  just  the  least 
bit  tinged  by  the  developer,  when  the  plate 
should  be  removed,  rinsed  and  thoroughly  fixed. 

This  same  method  of  procedure  will  often 
yield  fine  slides  from  negatives  which  are  so  thin 
that  paper  prints  from  them  are  an  impossi- 
bility. Very  intense  negatives  yield  but  fair 
slides  at  best,  excepting  those  intended  for  line 
work,  and  the  like.  The  proper  method,  with 
the  exception  noted,  is  long  exposure  and  weak 
developer. 


40 


All  experiments  of  this  kind  should  be  de- 
ferred until  the  reader  is  quite  expert  in  making 
fair  slides  from  good  negatives.  Like  all  good 
things,  the  contact  method  has  its  limitations. 
It  is  confined  to  the  use  of  negatives  with  images 
of  the  proper  size.  As  the  largest  opening  in  a 
standard  lantern  mat  is  3X2I  inches,  the  size  of 
the  image  must  conform  to  that.  Frequently  the 
image  is  too  large,  even  when  within  these  limits, 
and  produces  a very  inartistic,  crowded  effect 
when  projected  upon  a screen.  The  very  oppo- 
site sometimes  occurs,  but  the  former  is  so  omni- 
present that  it  is  really  a tremendous  fault. 
Often  the  immense  size  of  a certain  object  is 
toned  down  by  the  proportional  dimensions  of 
others  near  it.  If  there  happen  to  be  figures  in 
the  scene,  they  appear  as  mammoths.  The 
author  once  saw  upon  a screen  the  image  of  a 
dog  which  measured  21  feet  in  length.  This  was 
followed  by  Niagara  Falls,  not  quite  12  feet  long 
and  about  2 feet  high,  not  half  big  enough  to 
wet  the  dog.  It  is  a common  thing  to  see  human 
faces  appear  10  or  12  feet  in  circumference. 
The  incongruity  of  such  things  is  apparent,  and 
can  only  be  avoided  by  making  negatives  which 
are  suitable  for  slide  purposes,  or  by  calling  to 
our  aid  the  camera  method. 


CHAPTER  II. 

The  Camera  Method. 

THIS  method  requires  a camera  with  a long 
bed  and  bellows  to  match,  a lens  of  4 or  5 
inches’  focus,  and  an  adjustable  hood,  projecting 
in  front  of  the  lens  in  such  a way  that  it  extends 
to  the  frame  which  holds  the  negative,  so  that 
only  those  rays  of  light  which  pass  through  the 
negative  can  enter  the  lens. 


The  most  convenient  apparatus  for  this  work 
is  Anthony’s  lantern-slide  camera,  made  at  the 
suggestion  of  the  author. 


Anthony’s  Lantern-Slide  Camera. 


The  frame  carriage  for  the  ground-glass  and 
the  plate-holder  may  be  oscillated  within  certain 
limits,  so  that  the  image  on  the  slide  may  be 
perfectly  vertical,  even  if  that  on  the  negative  is 
askew. 


42 


This  camera  is  adapted  to  the  use  of  4x5 
negatives,  either  horizontally  or  vertically.  All 
its  parts  are  adjustable,  enabling  one  to  enlarge 
or-  reduce  the  size  of  the  image  at  pleasure. 
A flap  shutter  is  placed  just  back  of  the  lens 
frame,  with  an  indicator  which  shows  whether 
the  lens  is  open  or  closed.  This  is  an  excellent 
piece  of  apparatus,  and  is  not  expensive. 

Larger  cameras  are  manufactured,  so  that 
negatives  of  any  size  may  be  reduced  to  the 
proper  lantern-slide  size. 

When  a slide  is  to  be  made  in  this  camera, 
the  lens  is  first  screwed  into  its  front  board  and 
put  in  place;  the  negative  is  placed  in  the  frame 
at  the  end  of  the  camera  farthest  from  the 
ground-glass,  in  such  a way  that  the  gelatine  side 
is  toward  the  lens  and  the  image  is  upside  down. 

Then  place  the  camera  against  a window  at 
such  an  angle  that  it  points  directly  toward  the 
sky  (not  the  sun),  resting  the  lower  end  upon  a 
table,  or  it  may  be  directed  toward  a large  piece 
of  white  cardboard  brilliantly  illuminated  by 
daylight. 

The  lens  frame  is  then  pulled  back  from  the 
negative  the  distance  which  the  lens  requires  to 
form  the  image  of  the  desired  size.  This  dis- 
tance depends  upon  the  focus  of  the  lens,  and 
must  be  ascertained  by  experiment.  Suppose  it 
to  be  14  inches.  Then  move  the  ground-glass 
carriage  back  and  forth  until  the  image  upon 
the  ground-glass  is  very  sharp.  This  image 
will  be  right  side  up,  but  right  for  left  as  one 
sees  himself  in  a mirror.  If  the  image  is  too 


43 


large,  the  lens  must  be  moved  farther  from  the 
negative  and  the  focus  obtained  again.  If  too 
small,  the  lens  must  be  pushed  nearer  to  the 
negative  and  the  focus  adjusted,  again.  After 
the  camera  is  once  nicely  adjusted  for  the  aver- 
age negative,  the  positions  of  the  lens  frame  and 


Camera  Method. — Daylight. 

ground-glass  carriage  should  be  marked  in  order 
that  time  may  be  saved  on  some  future  occasion. 

A small  stop  or  diaphragm  should  then  be 
placed  in  the  lens,  for  two  reasons  : it  makes  the 
image  very  sharp,  and  it  increases  the  time  of 
exposure,  which  is  convenient  when  working  by 
daylight. 


44 


When  the  camera  is  pointed  at  the  sky  there 
is  a certainty  that  the  negative  will  be  evenly 
illuminated,  whereas  care  must  be  taken  if  the 
light  is  reflected  from  a white  screen.  The 
screen  must  be  adjusted  at  such  an  angle  that 
the  light  will  be  reflected  directly  through  all 
parts  of  the  negative  equally,  and  the  screen  or 
cardboard  must  not  be  too  near  the  negative. 
If  it  is,  a nice  image  of  it  will  appear  on  the 
slide  together  with  that  of  the  negative,  and 
will  probably  give  rise  to  “cuss  words.” 

Having  secured  a satisfactory  illumination, 
the  shutter  is  closed.  A slide  plate  is  put  into 
the  little  plate-holder  in  the  darkroom  by  non- 
actinic  light. 

The  holder  is  then  placed  in  its  proper  place 
in  the  camera,  the  slide  drawn,  and  the  exposure 
given  by  turning  the  shutter. 

The  length  of  exposure  depends  upon  the  lens 
used,  the  size  of  the  stop  or  diaphragm,  the  size 
of  the  image,  the  negative,  the  time  of  day,  the 
season  of  the  year,  and,  lastly,  the  state  of  the 
weather  or  of  the  sky.  Direct  sunlight  should 
not  be  used. 

The  only  invariable  quantities  are  the  lens,  its 
stop  and  the  standard  negative  and  developer. 
All  the  others  are  unreliable,  and  have  to  be 
tested  by  many  experiments. 

This  method  must  not  be  attempted  by  those 
who  are  not  able  to  make  a good  slide  by  the 
contact  method. 

To  illustrate  the  extreme  variability  of  day- 
light, the  exposures  given  upon  one  negative, 


45 


just  for  experimental  purposes,  will  be  out- 
lined. 

January  7th. — Clear,  at  noon,  one  minute  ; 
3 p.m.,  one  and  a half  minutes. 

January  8th. — Stormy,  at  noon,  two  minutes  ; 
at  3 p.m.,  four  minutes. 

January  9th. — Cloudy,  at  noon,  one  and  one- 
fifth  minutes  ; at  3 p.m.,  two  and  a half  minutes. 

January  10th. — Cloudy,  at  noon,  two  minutes  ; 
at  3 p.m.,  five  minutes. 

January  12  th. — Clear,  at  noon,  forty-five 
seconds  ; at  3 p.m.,  one  minute. 

January  18th. — Clear,  at  noon,  forty-five 
seconds  ; at  3 p.m.,  one  minute  ; at  4 p.m.,  two 
and  a half  minutes  ; at  5 p.m.,  seven  minutes. 

Lens,  Dallmeyer  4x5  rapid  rectilinear. 

Stop,  7/64. 

Plate,  Cramer  lantern  slide. 

With  an  ordinary  negative  a lens  of  the  rapid 
rectilinear  type  with  a small  stop,//64,  and  upon 
a clear  day  at  noon  in  J anuary,  an  exposure  of 
one  minute  should  be  tried  ; in  March,  a little 
less  ; in  May  half  the  time  will  suffice,  etc.,  etc. 

Using  such  a small  stop,  the  variation  of  a 
few  seconds  in  the  exposure  either  way  will  not 
amount  to  much,  because  the  plates  are  quite 
slow. 

The  standard  developer  for  this  work  is  4 
ounces  Anthony’s  hydroquinone  developer  plus  2 
ounces  of  water  and  no  bromide.  The  develop- 
ment should  be  carried  on  exactly  as  directed 
for  the  contact  method.  If  the  exposure  was  too 
long,  the  plate  will  develop  rapidly,  and  will  be 


46 


smoky  ; if  it  was  too  short,  the  plate  will  come 
up  to  a certain  point  and  stop,  and  all  the  dodges 
in  the  world  wont  help  matters  in  the  least. 

To  use  the  camera  method  by  gaslight,  another 
and  a rather  expensive  piece  of  apparatus  is 
needed,  and  that  is  a condensing  lens  of  greater 
diameter  than  the  diagonal  of  the  negative. 


Camera  Method. — Artificial  Light. 

The  author’s  apparatus  is  arranged  as  follows  : 
The  Anthony  lantern-slide  camera  is  adjusted  as 
if  for  daylight,  and  placed  upon  a large  table. 
The  negative  is  put  in  place,  and  a pair  of  8-inch 
plano-convex  lenses,  called  a condenser,  ad- 
justed in  front  of,  and  as  near  as  possible  to, 
the  negative.  A Welsbach  incandescent  gas 


47 


burner  is  then  adjusted  before  the  condenser,  so 
that  the  image  on  the  ground-glass  is  evenly 
illuminated.  Some  care  is  necessary  that  the 
lens,  the  negative,  the  condenser  and  the  gas- 
light are  properly  centered,  in  order  to  obtain 
an  equal  illumination. 

This  arrangement  is  nothing  but  a modified 
magic  lantern,  using  the  sensitive  slide  plate  as 
a screen.  The  exposures  are  regulated  by  the 
flap  shutter  as  before.  The  great  advantage  of 
this  arrangement  is  that  the  light  never  varies 
and  the  results  are  uniform. 

The  Welsbach  burner  yields  a beautiful,  power- 
ful white  light,  and  has  only  one  drawback,  and 
that  is  its  delicacy.  The  carbon  net  or  cone  is 
so  delicate  that  a sudden  jar  will  break  it  into 
thousands  of  pieces. 


CHAPTER  III. 


Diseases  and  Remedies. 

SOMETIMES  the  slide  is  beautiful,  except  for 
a slight  haze  or  fog , caused  often  by  over- 
exposure and  sometimes  by  too  warm  a de- 
veloper. This  may  be  removed  without  injuring 
the  slide  by  a careful  and  slow  application  of 
the  following  medicine:  Dissolve  24  grains  of 

hyposulphite  of  soda  in  1 ounce  of  water.  To 
this  add  from  three  to  ten  drops  of  a satu- 
rated solution  of  red  prussiate  of  potash.  This 
should  be  added,  drop  by  drop,  just  before  it  is 
to  be  used,  because  the  mixture  does  not  keep 
longer  than  fifteen  or  twenty  minutes,  and 
should  never  be  used  except  when  freshly 
mixed.  This  mixture  forms  a clearing  and 
reducing  solution,  the  active  power  of  which 
depends  entirely  upon  the  amount  of  potash 
added.  The  best  results  are  obtained  when  it 
is  so  weak  that  two  or  three  applications  are 
necessary  before  any  effect  is  seen. 

After  slides  have  been  once  dried,  they  do  not 
respond  with  any  degree  of  comfort  to  this 
treatment.  It  is  best  to  apply  it  just  after  the 
plate  has  been  removed  from  the  hypo  and 
rinsed  off  once  or  twice.  Running  water  should 
be  convenient,  so  that  the  action  may  be  checked 
at  any  moment.  Experiments  upon  worthless 


WEST  GATE,  NURNBERG. 


D.  L.  Elmendorf. 


49 


plates  should  precede  any  attempts  on  a good 
slide. 

To  apply  this  remedy  a J-inch  camel’s-hair 
brush  should  be  dipped  into  the  mixture  and 
then  brushed  quickly,  but  gently,  over  the  wet 
slide  in  every  direction,  while  in  a horizontal 
position;  after  which,  the  slide  should  be  held 
under  the  tap  for  a moment,  and  then  ex- 
amined. It  is  well  to  have  the  brush  full  of  the 
mixture  before  applying;  otherwise,  streaks  may 
appear.  If  not  cleared  enough,  repeat  the  opera- 
tion. By  using  a little  judgment  one  part  of 
the  slide  may  be  reduced  more  than  another  at 
pleasure. 

Remember  that  the  action  will  continue  for  a 
short  time  after  the  slide  is  placed  under  the 
tap.  After  treatment,  the  slide  should  be 
washed  for  a few  minutes,  and  then  placed  in 
the  alum  solution,  and  then  washed  thoroughly. 

2.  Sometimes  a slight  veil  or  fog  is  caused  by 
the  water  used  either  in  the  making  up  of  the 
developer  or  for  washing  the  plates.  Croton 
water  is  very  liable  to  produce  this  effect. 
Remedy — dissolve  \ an  ounce  of  citrate  of  soda 
in  6 ounces  of  water,  and  pour  this  solution  on 
and  off  the  plate.  Sometimes  it  is  necessary  to 
rub  the  plate  with  a tuft  of  absorbent  cotton 
wetted  with  the  solution. 

3.  A sky  full  of  opaque  and  transparent  spots. 
The  opaque  spots  are  sometimes  in  the  emulsion 
itself ; they  are  then  incurable,  but  generally 
they  are  caused  by  minute  transparent  places 
in  the  negative,  called  “pinholes.”  Chemical 


50 


dust,  mentioned  before,  is  another  source  of  this 
evil. 

Transparent  spots  are  often  caused  by  poor 
manipulations  in  the  development,  little  bubbles 
of  air  on  the  plate  preventing  the  developer 
from  acting  on  those  portions  of  the  slide. 

They  may  be  prevented  by  rocking  the  tray 
violently  when  the  plates  are  first  immersed. 
Sometimes  it  is  necessary  to  rub  the  plate  with 
the  ball  of  a finger,  which  is  wet  with  developer, 
but  only  the  gentlest  pressure  must  be  used  or 
the  film  will  be  scratched.  A perfectly  clean 
camel’s-hair  brush  may  be  used,  if  it  is  very 
soft,  but  the  delicate  touch  of  the  finger  is 
better. 

It  is  sometimes  possible  to  clear  up  such  a sky, 
without  injuring  the  rest  of  the  slide,  by  careful 
applications  of  the  red  potash  mixture  ; but  the 
author  prefers  to  block  out  the  sky  of  the 
negative  with  Strauss  marl  and  make  another 
exposure. 

4.  The  slide  is  very  thin. 

There  are  several  causes  of  this  disease ; 
under  and  over  exposure  bring  it  on,  and  under- 
development aggravates  it.  Correct  exposure, 
but  not  long  enough  development,  will  also 
result  in  thinness. 

Remedy — make  a new  slide. 

Having  tried  all  the  patent  medicines  labeled 
“ superb  formulas”  for  the  intensification  of 
slides,  and  failing  in  every  case  to  make  the 
consumptive  slide  equal  in  any  respect  to  a new 
one  exposed  and  developed  correctly,  the  author 


51 


recommends  the  above  remedy  as  a safe  and 
sure  one. 

Intensifies  are  like  procrastination. 

5.  The  slide  is  too  thick  and  dark.  This  is 
the  result  of  over-development.  Take  a small 
tray,  fill  it  with  cold  water  to  a depth  of  one- 
fourth  of  an  inch,  and  add  to  the  water  ten 
or  twenty  drops  of  the  red  potash  solution 
and  mix  it  well.  Place  the  thick  slide,  as  it 
comes  from  the  hypo,  without  rinsing  it  at 
all,  in  this  tray,  removing  it  every  few  moments 
for  examination.  If  no  action  takes  place,  re- 
move the  plate,  add  more  potash  solution,  mix 
well,  and  then  immerse  the  plate  again.  If 
properly  adjusted  this  prescription  will  reduce 
the  thickness  of  the  whole  plate  to  any  desired 
extent.  After  treatment,  wash  under  the  tap 
for  two  or  three  minutes,  place  it  in  the  alum 
solution  for  the  usual  time,  and  then  proceed 
with  the  final  washing. 

6.  Curious  stains  on  one  or  more  corners  of 
the  plate,  caused  invariably  by  some  substance 
foreign  to  the  developer  which  had  not  been  re- 
moved from  the  fingers  which  held  the  plate. 

Hypo,  alum  and  red  prussiate  of  potash  take 
fiendish  delight  in  producing  these  beauty  spots  ; 
so  beware  of  their  pranks. 

Remedy — none.  Prevention  is  the  best 
policy. 

7.  Yellow  tinge  to  the  whole  plate,  often 
caused  by  impure  water,  sometimes  by  old 
and  decomposed  developer  or  hypo  solution.  It 
may  be  remedied,  but  not  always,  by  an  appli- 


52 


cation  of  the  red  potash  solution  as  in  the  first 
case. 

An  application  of  the  citrate  of  soda  will 
sometimes  relieve  it. 

Weak  hydrochloric  acid  will  clear  the  plate, 
but  is  liable  to  take  film  and  all  with  it. 

This  yellow  tinge  is  sometimes  inherent  in 
the  emulsion  itself,  and  is  hopelessly  incurable. 
Get  other  plates.. 

8.  Frilling.  This  peculiar  disease  is  often 
caused  by  exposing  the  gelatine  film  to  sudden 
changes  of  temperature.  If  a plate  be  removed 
from  a developer  which  is  70  degrees  and 
plunged  into  water  or  hypo  at  45  degrees  tem- 
perature, the  chances  are  that  the  edges  of  the 
plate  will  frill.  The  gelatine  expands  and  con- 
tracts more  rapidly  than  glass,  and  therefore 
wrenches  itself  from  its  support,  and  seems  to 
swell  up  in  places  to  such  a degree  that  it  loses 
its  power  of  contracting  again  to  its  original 
size.  The  alum  solution  will  sometimes  stop 
this,  but  will  not  remedy  it.  Lantern-slide 
plates  are  not  so  liable  to  frill  as  the  more  rapid 
negative  plates,  but  it  will  happen  on  any  plate 
which  was  not  properly  cleaned  before  the 
emulsion  was  applied. 

There  are  many  other  diseases  which  are  the 
results  of  careless  manipulations,  dirty  fingers 
or  apparatus  and  unpardonable  thoughtlessness, 
which  may  never  trouble  a careful  worker. 

Only  a short  diagnosis  of  the  evils,  common 
to  all,  has  been  attempted. 

Once  again,  allow  sad  experience  to  reassert 


53 


that  time,  temper  and  money  are  saved  by 
making  another  exposure  if  the  first  was  de- 
fective in  any  respect. 

Poor  slides  often  make  excellent  cover  glasses, 
if  they  are  free  from  bubbles  and  are  well 
cleaned. 


CHAPTER  IV. 

Testing  Slides. 

SLIDES  which  appear  to  be  very  good  while 
wet  should  be  carefully  examined  when  dry. 
Generally  they  gain  in  density  as  they  dry,  es- 
pecially if  they  are  dried  rapidly. 

A very  nice  little  instrument  for  testing  slides 
is  called  a lan- 
ternoscope  (see 
cut),  which  con- 
sists of  a frame 
holding  a con- 
vex lens,  fast- 
en e d to  a 
folding  bed  on 
which  slides  an- 
other frame  made  to  hold  a lantern  slide.  This 
is  connected  with  the  lens  frame  by  a bellows 
which  excludes  all  light  except  that  which 
passes  through  the  slide.  Upon  looking  through 
the  lens  at  a slide  inserted  in  place,  an  enlarged 
image  is  seen,  and  the  general  quality  of  the 
slide  may  be  judged  with  great  ease  and 
pleasure. 

When  one  does  not  wish  to  go  to  the  trouble 
of  lighting  up  the  lantern,  this  little  lanterno- 
scope  affords  a convenient  means  of  showing 
slides  to  friends  or  to  pupils  in  a class-room. 
The  best  test,  however,  is  the  lantern  itself. 


55 


when  under  the  conditions  that  the  pictures  are 
to  be  afterwards  exhibited. 

Slides  which  are  just  right  for  a lantern  with 
oil  light  are  not  so  for  the  oxyhydrogen  jet. 
Again,  those  which  are  suitable  for  the  latter 
are  not  the  finest  for  the  electric  arc  light. 

Still  further  discrimination  must  be  made 
when  the  size  of  the  screen  is  considered.  A 
slide  which  appears  well  upon  a 6-foot  screen 
will  be  disappointing  on  a 20-foot  screen,  ap- 
pearing too  dark  because  it  is  too  thick.  If 
another  slide,  but  not  so  thick,  from  the  same 
negative,  be  then  projected  upon  the  screen, 
the  difference  will  be  apparent;  whereas,  if  the 
same  pair  of  slides  were  judged  upon  the  small 
screen,  the  former  would  be  pronounced 
superior. 

These  points  are  rarely  taken  into  considera- 
tion by  judges  of  “ prize  ” slides,  yet  they  must 
be  carefully  weighed  by  the  one  who  desires 
perfection  on  the  screen. 

Oil  lamps  of  the  best  construction  will  project 
enough  light  through  suitable  slides  to  illuminate 
an  8-foot  screen  fairly  well,  but  it  is  impossible 
to  get  a sharp  image  with  any  form  of  oil  lamp 
because  the  source  of  light  is  not  an  approximate 
point. 

The  oxyhydrogen  jet  will  illuminate  slides 
adapted  to  it  when  magnified  up  to  20  feet 
square.  For  many  reasons  the  author  prefers 
this  form  of  light  to  any  other  at  present. 

The  electric  arc  should  be  used  when  any 
greater  magnification  than  this  is  desired.  The 


56 


author  deprecates  the  use  of  the  electric  arc  for 
projecting  lantern  slides  upon  small  screens, 
and  considers  the  effects  very  glaring  and  un- 
pleasantly cold. 

The  arc  light  is  superb  for  microscopic  pro- 
jections and  for  slide  projections  upon  enormous 
screens  or  upon  small  screens  in  the  class-room 
in  ordinary  diffused  daylight. 

As  many  may  prefer  to  make  up  their  own 
developer,  several  formulas  will  be  given  as 
used  by  the  author.  Some  may  be  able  to  get 
better  results  from  other  formulas,  and  they  had 
better  do  so ; the  author  has  not.  There  is 
nothing  original  about  the  following  devel- 


opers • 

I. 

Saturated  solution  of  oxalate  of 

potash 5 ounces  (fluid). 

Saturated  solution  of  iron  sul- 
phate   i ounce  “ 


Pour  the  iron  into  the  oxalate,  never  vice 
versa , and  add  three  to  five  drops  of  saturated 
solution  of  bromide  of  potash. 

This  developer  gives  beautiful  results,  rang- 
ing from  gray  to  brown,  according  to  the  expos- 
ure, but  will  not  keep  long  after  mixing. 

II. — Hydroquinone  Developer. 

A. 


Hydroquinone 15  grains. 

Sulphite  of  soda  crystals 44  “ 

Bromide  of  potash 13  “ 


Water  (pure)  to  make  a total  bulk  of  10  ounces. 


57 


B. 


Carbonate  of  soda 90  grains. 

Carbonate  of  potash 90  “ 


Water  (pure)  to  make  a total  bulk  of  10  ounces. 

Take  equal  portions  of  A and  B,  to  form  a 
normal  developer. 

This  is  the  most  convenient  of  all  developers, 
as  it  may  be  used  until  it  begins  to  act  too  slow, 
when  half  of  it  should  be  thrown  away,  the  re- 
mainder filtered,  and  then  an  equal  bulk  of  fresh 
developer  added. 

When  made  with  pure  chemicals  and  with 
distilled  water,  it  will  keep  indefinitely. 


III. — Metol. 


Water 60  ounces. 

Sulphite  of  soda  crystals 6 “ 

Metol 1 ounce. 

Bicarbonate  of  soda 3 ounces. 


Bromide  of  potash  (10  per  cent.),  a few  drops. 

Dissolve  in  the  given  order. 

This  is  the  Cramer  formula,  and  works  well, 
but  requires  a shorter  exposure  than  either 
I or  II. 

It  is  often  necessary  to  project  maps,  dia- 
grams, formulas,  special  solutions  of  problems, 
comic  drawings  and  the  like  upon  a screen  at 
short  notice. 

In  order  to  make  a photographic  slide  of  any 
of  these  subjects,  the  drawing  must  first  be 
photographed  and  the  slide  then  made  from  the 
negative,  a long  and  expensive  process  when 
the  slide  is  for  temporary  use  only. 


58 


During  a long  experience  in  teaching  the 
deaf,  using  the  lantern  as  a means  of  illustrat- 
ing the  various  branches  of  study,  such  as 
geography,  history,  physics,  etc.,  and  for  the 
purpose  of  entertainment,  some  means  of  writing 
upon  the  slides  was  necessary.  In  a happy 
moment,  carbon  transfer  paper  was  thought  of 
and  tried  with  great  success. 

By  simply  laying  the  carbon  paper  upon  the 
clean  cover  glass  of  the  slide  and  then  super- 
posing a piece  of  thin,  smooth-finished  paper, 
any  inscription  written  on  the  paper  with  the 
sharp  point  of  a hard  pencil  will  be  found  per- 
fectly transferred  upon  the  glass  if  the  latter 
was  perfectly  cleaned  beforehand.  Comic 
drawings,  in  fact  anything  of  the  kind  of  suit- 
able size,  may  be  transferred  by  this  simple 
process  of  tracing. 

The  transfer  slide  should  be  matted  and 
mounted  as  an  ordinary  slide.  By  transferring 
upon  a gelatine  surface  which  has  been  treated 
with  alum,  color  may  be  applied. 


CHAPTER  V. 

How  to  Color  Slides. 

“T^OOLS  step  in  where  angels  fear  to  tread” 
]L  expresses  the  author’s  feelings  when 
about  to  attempt  the  description  of  that  which 
is  indescribable. 

The  first  rule  to  be  learned  and  obeyed  is, 
don’t  color  slides,  but  tint  them. 

Unless  one  has  real  artistic  feeling  and  a knowl- 
edge of  tone  and  color,  the  slides  had  better 
remain  as  the  developer  made  them. 

Having  tried  every  kind  of  pigment,  paint 
and  coloring  matter  obtainable,  the  author  has 
settled  down  to  a few  aniline  dyes,  which  have 
now  stood  the  test  of  ten  years  very  well. 
These  were  not  chosen  because  they  are  easy  to 
apply — in  fact,  they  are  much  more  difficult  to 
use  than  some  of  the  pigments  mixed  with 
Canada  balsam,  Damar  varnish  and  other  medi- 
ums— but  because  of  their  brilliancy  and  won- 
derful lack  of  “grain,”  even  when  greatly 
magnified. 

The  wail  from  some  quarters  that  aniline 
colors  are  fugitive  is  quite  true  in  a general 
sense,  but  by  accident  the  author  stumbled  upon 
a certain  addition  which  not  only  makes  the 
colors  quite  permanent,  but  also  prevents 
“ creeping  ” when  properly  applied.  After  care- 
ful tests  for  ten  years,  the  author  now  feels  that 


60 


the  colors  are  reliable,  and  will  soon  prepare 
them  in  quantity  for  the  use  of  others. 

Unfortunately  they  are  expensive,  but  when 
the  quantity  necessary  for  ten  slides  is  meas- 
ured and  the  cost  of  the  same  computed,  this 
bugbear  disappears.  Ten  drops  of  some  of  the 
colors  will  color  fifty  slides. 

The  principal  colors  prepared  by  the  author 
are  : 

1.  Light  yellow. 

2.  Dark  yellow. 

3.  Orange. 

4.  Crimson. 

5.  Vermilion. 

6.  Dark  brown. 

7.  Maroon. 

8.  Blue  No.  1. 

9.  Blue  No.  2. 

10.  Violet. 

These  ten  colors  are  the  elements  from  which 
countless  tints  may  be  formed  by  mixing  one 
with  another  in  various  proportions. 

The  colors  are  very  concentrated,  and  most 
of  them  should  be  diluted  with  clear  water 
before  applying. 

The  amount  of  water  to  be  added  must  be 
ascertained  by  experiment  in  order  to  obtain 
the  depth  or  strength  of  color  desired. 

Light  yellow  and  orange  mix  in  all  propor- 
tions, forming  various  tints.  The  mixture 
should  be  diluted  with  about  an  equal  quantity 
of  water  unless  powerful  colors  are  desired. 


D.  L.  Elmendorf. 


A WHITE-ASH  BREEZE,  HOLLAND. 


61 


Light  yellow  and  crimson  form  useful  tints 
for  evening  sky  effects,  and  for  flesh  tints  of  a 
brownish  tendency.  Should  be  diluted  before 
applying. 

Light  or  dark  yellow  and  vermilion  in  various 
proportions  give  endless  gradations  from  the 
one  to  the  other,  and  this  is  the  chief  mixture 
for  flesh  tints.  Vermilion  is  the  most  powerful 
of  all  the  colors,  and  should  be  diluted  very 
much. 

Light  yellow  and  blue  No.  i mix  in  any  pro- 
portions, forming  pale  greens.  Should  not  be 
diluted.  By  adding  some  dark  yellow,  warmer 
and  more  brilliant  greens  are  obtained. 

The  coldness  or  warmth  of  the  green  depends 
upon  the  amount  of  yellow  added  to  the  blue. 

Dark  yellow  and  blue  No.  2 yield  intense 
greens,  and  are  especially  useful  in  contrast 
with  those  of  blue  No.  1.  Should  not  be  diluted 
except  in  special  cases. 

Orange  and  blue  No.  2 yield  a splendid  variety 
of  earthy  yellows  and  olive  greens,  which  are 
very  valuable  for  foregrounds,  dead  grass,  etc. 

A very  slight  addition  of  vermilion  gives  rich 
ochre  tints.  Should  be  diluted  as  necessary. 

After  applying  these  orange  and  blue  mixt- 
ures it  is  well  to  wash  off  the  slide  with  the 
same  brush  wet  with  water  only,  to  prevent  any 
deposit,  which  sometimes  occurs. 

Maroon  and  the  yellows  produce  numerous 
tints,  passing  from  yellow  and  brown  to  maroon. 
Should  be  diluted. 

Dark  brown  is  a reddish  brown,  and  should  be 


62 


diluted  only  a little,  say  with  equal  parts  of 
water,  unless  a very  pale  tint  is  required.  It  will 
mix  with  other  colors  for  a variety  of  tints. 

Crimson  should  always  be  diluted  with  a large 
quantity  of  water. 

Blue  No.  i,  when  diluted  with  5 to  10  parts 
of  water,  is  suitable  for  skies  and  water,  remem- 
bering that  water  reflects  the  sky  and  other 
objects  above  it,  so  chat  plain  blue  will  not 
always  answer  for  water,  even  when  suitable 
for  the  sky. 

Each  portion  of  the  day  and  the  year  has  its 
own  peculiar  tints,  both  in  sky  and  water,  nor 
are  all  portions  of  either  alike  at  the  same  time. 
One  must  study  these  wonderful  color  effects  in 
Nature  if  any  realistic  results  are  to  be  hoped 
for. 

Blue  No.  2 is  a greenish  blue,  suitable  when 
diluted  for  either  sky  or  water  under  certain 
conditions  of  atmosphere  and  light. 

Violet,  although  apparently  a powerful  color, 
is  not  so,  and  is  difficult  to  manipulate.  It  does 
not  mix  well  with  other  colors,  but  beautiful 
purple  tints  may  be  obtained  by  first  applying 
the  violet  to  the  part  to  be  colored,  and  then, 
after  it  is  set,  but  not  dry,  applying  a very  weak 
solution  of  vermilion  until  the  desired  tint  is 
obtained,  a process  of  blending  which  is  quite 
difficult  to  the  uninitiated. 

With  these  few  hints  as  to  mixing  the  colons 
for  various  tints,  the  author  hopes  that  the  way 
is  made  clear.  Thousands  of  tints  may  be  ob- 
tained after  the  same  manner. 


63 


Requisites. 

i.  A nest  of  white  porcelain  saucers  should 
be  obtained,  such  as  microscopists  use.  They 
are  invaluable  for  slide  work,  as  each  saucer 
forms  a cover  for  the  other,  so  that  all  dust  is 
excluded. 


2.  Each  color  should  have  a brush  of  its  own, 
which  should  never  be  used  for  any  other.  The 
author  uses  three  each  for  the  majority  of 
colors,  Nos.  2,  3,  and  4,  soft  round  camel’s  hair. 


64 


They  should  be  well  made,  and  come  to  a point 
when  wet. 

For  skies  and  water,  or  for  general  tints  and 
blending,  half-inch  flat  camel's-hair  brushes 
should  be  used. 

3.  A large  glass,  capable  of  holding  a pint  of 
water,  should  be  at  hand,  convenient  for  imme- 
diate use  at  all  times. 


4.  For  the  purpose  of  adding  water  to  the 
colors,  there  is  nothing  better  than  a rubber 
pipette,  often  used  as  medicine  droppers,  or  for 
filling  fountain  pens. 

5.  A clean  cloth  attached  to  the  table  for  the 
purpose  of  wiping  color  from  brushes. 

6.  A retouching  frame,  such  as  is  used  for  re- 
touching negatives  with  a very  fine  ground- 
glass. 


65 


The  author  colors  all  his  slides  by  means  of  a 
Welsbach  incandescent  gas  burner,  which  gives 
a quality  of  light  almost  exactly  like  the  oxyhy- 
drogen  jet. 

7.  A room  without  hangings,  draperies,  or 
carpet.  The  floor  should  be  dampened  before 
beginning  the  coloring.  A room  especially  ar 
ranged  for  the  purpose  is  advisable  if  the  col- 
orist desires  any  comfort  at  all  in  the  work. 
Dust  is  a most  vexatious  nuisance.  One  little 
particle  falling  on  the  wet  slide  will  stick  closer 
than  a brother,  and  will  be  painfully  evident  on 
the  screen. 

The  gelatine  surface  of  the  slide  takes  the 
colors  well  if  it  has  been  treated  with  a satu- 
rated solution  of  alum  as  directed  under  de- 
velopment. The  slide  to  be  colored  should  be 
placed  on  the  ground-glass  of  the  retouching 
frame  with  a narrow  strip  of  wood,  about  an 
eighth  of  an  inch  thick,  under  the  lower  edge 
so  as  to  raise  the  slide  slightly  from  the  ground- 
glass,  in  order  to  prevent  capillary  attraction. 
The  mirror  and  light  should  be  adjusted  so  that 
the  slide  is  properly  illuminated.  The  sky 
should  be  colored  first,  and  it  is  sometimes  ad- 
visable to  turn  the  sky  toward  the  bottom  or 
sideways  during  this  part  of  the  work  ; “ gump- 
tion ” will  suggest  the  most  convenient  posi- 
tions. Put  a few  drops  of  blue  No.  1 in  a saucer 
and  dilute  it  with  8 parts  of  water,  more  or 
less.  Take  the  half -inch  blue  brush,  wet  it  full 
of  clear  water  and  moisten  the  sky  evenly  and 
thoroughly,  using  plenty  of  water  in  the  brush. 


66 


If  the  brush  is  not  full  of  water  it  is  liable  to 
stick  to  the  gelatine  or  cause  lines.  Then  draw 
the  brush  between  the  thumb  and  forefinger  to 
remove  most  of  the  water,  dip  it  in  the  dilute 
blue  color  in  the  saucer,  and  brush  quickly  back 
and  forth  over  the  wet  sky. 

Don’t  allow  the  brush  to  stop  on  the  slide.  By 
using  dilute  color  and  applying  many  times,  a 
perfect  sky  may  be  obtained. 

When  a blended  sky  is  desired,  first  wet  the 
plate  as  before  and  take  the  half-inch  orange 
brush,  dip  it  in  a very  weak  solution  of  orange 
or  any  other  color  and  paint  the  lower  portion 
of  the  sky  with  it,  then  dip  the  brush,  still  full 
of  color,  in  clear  water  and  gradually  work  up 
toward  the  zenith  with  this  very  weak  color, 
then  wash  out  the  brush  in  water  and  blend 
from  the  bottom  to  the  top  of  the  sky.  Then 
take  the  blue  brush  and  wet  it  with  water,  dip 
it  in  the  dilute  blue  color  and  brush  across  the 
zenith  of  the  sky,  gradually  blending  the  blue 
down  about  half  way.  This  blending  operation 
is  very  difficult  to  describe  ; it  really  ought  to 
be  seen  to  be  thoroughly  understood.  The 
plate  should  be  turned  so  that  the  color  does 
not  flow  down  over  the  foreground. 

Large  expanses  of  water  are  treated  in  a 
similar  fashion. 

Any  number  of  harmonious  tints  may  be 
blended  in  the  same  way,  being  careful  to  blend 
the  colors  in  their  proper  order. 

The  author’s  method  is  to  color  the  skies  of 
several  slides  and  place  them  in  a drying  rack 


67 


to  dry  before  any  other  coloring  is  attempted. 

When  the  sky  is  dry,  other  portions  of  the 
slide  may  be  colored  by  applying  the  color  to 
the  dry  gelatine. 

Never  try  to  apply  another  color  to  the  slide 
until  the  first  one  has  dried,  unless  blending  is 
the  object  in  view.  In  coloring  trees,  first  give 
them  a general  pale  tint  of  green  and  then  work 
out  each  tree  in  detail  with  various  tints  of 
green. 

Detached  branches  of  trees,  and  conspicuous 
leaves  demand  careful  treatment,  which  needs 
long  practice,  a steady  hand,  and  an  accurate 
eye.  Flesh  needs  most  careful  treatment,  and 
careful  and  repeated  application  of  very  dilute 
colors,  until  the  desired  effect  is  gained,  is  the 
best  method.  It  is  not  always  necessary  to  color 
every  part  of  a slide.  Very  frequently  the  slide 
in  some  portions  presents  the  natural  appear- 
ance of  the  object,  and  color  would  only  detract 
from  the  general  effect. 

If  the  slides  are  colored  by  ordinary  daylight 
the  effects  will  be  rather  surprising  when  viewed 
at  night  by  means  of  the  lantern.  The  arc  light 
will  reproduce  the  colors  almost  similar  to  day 
light,  but  neither  oil  or  gas  will  accomplish  this 
for  physical  reasons  which  were  mentioned  in 
the  introduction.  Therefore  the  author  uses 
the  Welsbach  incandescent  gas  burner  as  the 
means  of  illumination.  Slides  should  be  colored 
for  the  light  used  in  projecting  them  on  the 
screen,  and  used  with  that  light  and  no  other. 

After  one  slide  has  been  colored  successfully, 


68 


so  that  the  worker  is  satisfied  with  its  effects  on 
the  screen,  other  slides  may  be  colored  by  ordi- 
nary daylight,  using  this  slide  as  a guide  to 
color. 

Night  effects  may  be  obtained,  by  developing 
the  slide  very  dark  and  then  coloring  the  whole 
with  blue  No.  i,  undiluted. 

In  mixing  the  colors,  pour  out  one  or  more 
drops  of  color  into  a saucer  and  add  water  by 
means  of  the  pipette.  Never  put  a brush  into 
the  bottle  of  color. 

In  conclusion,  allow  the  author  to  beseech 
anyone  without  “ an  eye  for  color  ” to  leave 
coloring  severely  alone. 

Some  may  be  like  the  Irishman  the  author 
met  last  summer  at  Killarney,  who,  when  ques- 
tioned as  to  the  benefits  of  Home  Rule  if  they 
got  it,  replied  : 

“We  don’t  know  thot,  but  we’re  bound  to 
have  it.” 


ANTHONY’S 
Lantern-Slide  Camera 


IS  WELL  MADE,  LIGHT  AND  SIMPLE 
OF  CONSTRUCTION. 


Has  an  oscillating  frame  carriage  for  ground- 
glass  and  plate-holder.  Can  be  used  also  for 
copying. 

Highly  endorsed  by  D.  L.  Elmendorf. 


Price,  - $12.00 

Special  holders,  - - - 1.50 

E.  A.  single  lens  for  above,  3.75 


For  sale  by  all  dealers  and  by 

E.  & H.  T.  ANTHONY  & CO., 

591  Broadway,  New  York. 


1 


A novel  and 
beautiful  con- 
trivance for 
viewing  lantern 
slides  without 
the  aid  of  the 
lantern.  Made 
of  finely  finished 
mahogany. 


Price,  - = $10.00 

ANTHONY'S  FOLDING  NEGATIVE  RACK. 


For  holding  24  plates  while  drying. 


vStrongly  made  and  very  useful. 


Price,  -----  40  cents. 

E.  & H.  T.  ANTHONY  & CO.,  591  Broadway,  New  York. 


11 


ANTHONY’S  PATENT 

I mproved  P rinting  F rames 

are  absolutely  unequaled.  A tongue 
and  groove  in  the  hinged  back  prevent 
the  fogging  of  the  plate  from  the  back. 


Padded  back,  spring  tally  for  recording 
number  of  prints,  celluloid  tablet,  and  springs 
of  the  best  quality. 


3i  x 4i 
4 x5 

4i  x 6^ 


PRICES: 

- $0-36  5x7 

- -38  5x8 


8 x 10 


.40 


6i  x 8i  - 
$°-75 


$0.50 

- -52 

.60 


E.  & H.  T.  ANTHONY  & CO., 
591  Broadway,  New  York. 
iii 


ANTHONY’S 


H YDROQUINONE  DEVELOPER. 


The  excellent  qualities  of  this  article  and  its 
convenience  for  use  are  possessed  by  no  other 
ready-prepared  developer  on  the  market. 

Highly  endorsed  by  Prof.  D.  L.  Elmendorf 
and  other  authorities. 


Price,  per  8 oz.  bottle,  - - 30  cents, 

per  pint  bottle,  - - - 55  “ 


are  known  the  world  over  as  the  purest  and 


most  reliable. 

Red  prussiate  of  potash,  per  oz.,  - .10 

Hyposulphite  of  soda,  per  lb.,  - - .08 

Alum,  per  lb.,  - - - - - .10 

Potassium  bromide,  per  oz.,  - - .12 

Acid  sulphite  of  soda,  per  pint,  - .40 


E.  & H.  T.  ANTHONY  & CO.,  591  Broadway,  New  York. 


IV 


LANTERN-SLIDE  BINDERS. 


These  are  black  gummed  strips  for  binding 
slides  and  will  be  found  very  useful. 


Price,  per  package  of  50,  - 15  cents. 


SHEPLIE’S  GUM  PAPER. 

Recommended  by  D.  L.  Elmendorf  for  bind- 
ing lantern  slides. 

Sold  in  rolls  containing  about  300  yards. 


Price,  per  roll,  - - 60  cents. 

Cover  Glass  for  Lantern  Slides. 

Thin  crystal  glass,  free  from  blemish,  and 
especially  made  for  lantern  slide  work  ; the  best 
glass,  being  of  the  proper  thickness. 


Price,  per  dozen,  - - 30  cents. 


CAMEL’S-HAIR  DUSTERS. 

For  dusting  plates.  Made  of  the  best 
material. 

1 inch,  - $0.20  I 2 inch,  - $0.40 

ii  “ - - -30  | 2$  “ - - .65 


E.  & H.  T.  ANTHONY  & CO.,  591  Broadway,  New  York. 


ELMENDORF’S 

Lantern-Slide  Colors. 


The  only  colors  that  will  give  satis- 
factory results  for  lantern-slide  tinting. 
Put  up  in  concentrated  form,  each  box 
containing  ten  bottles  of  color. 


COLO  RS. 


Light  yellow, 
Dark  yellow, 
Orange, 
Rose, 
Vermilion, 


Brown, 
Maroon, 
Blue  No.  i, 
Blue  No.  2, 
Violet. 


PRICE: 

No.  i,  - $i.5° 


For  Sale  by  all  Dealers  and 

E.  & H.  T.  Anthony  & Co., 

591  BROADWAY,  NEW  YORK. 


VI 


Criterion  Magic  Lanterns 

AND  StEREOPTICONS 

may  be  used  with  Oil,  Lime,  Welsbach 
Gas,  Incandescent  or  Arc  Electric  Light, 
interchangeably. 

N ew  Self-Focusing  Arc 
Electric  Lamps. 

Light  perfectly  centered  constantly. 
Used  in  many  institutions,  and  by  men 
of  highest  professional  standing. 
Correspondence  solicited. 

J.  B.  COLT  & CO., 

Patentees  and  Manufacturers, 

Main  Offices:  115  and  117  Nassau  Street,  New  York. 

AGENCIES  : 

33,  35  and  39  So.  10th  Street,  189  La  Salle  Street, 

Philadelphia,  Pa.  Chicago,  III. 

50  Bromfield  Street,  131  Post  Street, 

Boston,  Mass.  San  Francisco,  Cal. 


Cut  shows  Criterion  Lantern  with  Welsbach  Gas  Burner. 
SEND  FOR  CATALOGUE. 


VII 


GRIDIRON 

SATURATOR 

does  away  with  oil  lanterns.  No  need  to 
use  gas  or  hydrogen.  Only  oxygen 
required. 


Safe,  simple,  sure, ' portable,  powerful; 
can  be  used  in  any  ordinary  magic  lantern. 


PRICE,  - $30. 


SEND  FOR  CIRCULAR. 


E.  & H.  T.  ANTHONY  & CO., 

591  Broadway,  New  York. 


EVERYTHING  necessary  for  the  mak- 
ing of  negatives  and  lantern  slides 
will  be  found  in  our  revised,  illustrated 
catalogue.  Cameras  of  all  sizes  at  all 
prices,  Dallmeyer  Lenses,  Entrekin  Burn- 
ishers, and,  in  fact,  everything  and  any 
thing  necessary  to  the  professional  and 
amateur  photographer.  Publishers  of 

ANTHONY’S 

PHOTOGRAPHIC 

BULLETIN, 

a monthly  journal  for  photographers  ; 
price  per  copy,  2 5 cents  ; per  year,  $2. 


E.  & H.  T.  Anthony  & Co., 

591  Broadway,  New  York. 


IX 


4 


u GETTY  RESEARCH  INSTITUTE 

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